tidy-up: miscellaneous

- drop stray duplicate empty lines in docs, scripts, test data, include,
  examples, tests.
- drop duplicate PP parenthesis.
- curl-functions.m4: move literals to the right side in if expressions,
  to match rest of the source code.
- FAQ.md: delete language designator from an URL.
- packages: apply clang-format (OS400, VMS).
- scripts/schemetable.c: apply clang-format.
- data320: delete duplicate empty line that doesn't change the outcome.
- spacecheck: extend to check for duplicate empty lines
  (with exceptions.)
- fix whitespace nits

Closes #19936

docs/FAQ.md

@@ -827,7 +827,6 @@ chain.
 Details are also in [the SSL certificates
 document](https://curl.se/docs/sslcerts.html).
 
-
 ## Why is curl -R on Windows one hour off?
 
 Since curl 7.53.0 this issue should be fixed as long as curl was built with
@@ -891,7 +890,7 @@ the second. No more than three packets are sent, no matter how long the
 timeout is set.
 
 See option `TcpMaxConnectRetransmissions` on [this
-page](https://support.microsoft.com/bg-bg/topic/hotfix-enables-the-configuration-of-the-tcp-maximum-syn-retransmission-amount-in-windows-7-or-windows-server-2008-r2-1b6f8352-2c5f-58bb-ead7-2cf021407c8e).
+page](https://support.microsoft.com/topic/hotfix-enables-the-configuration-of-the-tcp-maximum-syn-retransmission-amount-in-windows-7-or-windows-server-2008-r2-1b6f8352-2c5f-58bb-ead7-2cf021407c8e).
 
 Also, even on non-Windows systems there may run a firewall or anti-virus
 software or similar that accepts the connection but does not actually do

docs/MANUAL.md

@@ -276,7 +276,6 @@ this:
 
     curl --trace my-trace.txt www.haxx.se
 
-
 ## Detailed Information
 
 Different protocols provide different ways of getting detailed information

docs/SSLCERTS.md

@@ -133,7 +133,6 @@ Apple SecTrust and your own file to be considered, use:
 
     curl --ca-native --cacert mycerts.pem https://example.com
 
-
 #### Other Combinations
 
 How well the use of native CA stores work in all other combinations depends

docs/TODO.md

@@ -398,7 +398,6 @@ honest a bit of a hack.
 Please see the following thread for more information:
 https://curl.se/mail/lib-2012-05/0178.html
 
-
 # POP3
 
 ## Enhanced capability support

docs/TheArtOfHttpScripting.md

@@ -198,7 +198,6 @@ SPDX-License-Identifier: curl
 
     curl --data name=curl https://url1.example.com https://url2.example.com
 
-
 ## Multiple HTTP methods in a single command line
 
  Sometimes you need to operate on several URLs in a single command line and do

docs/examples/ephiperfifo.c

@@ -41,7 +41,6 @@ Whenever there is input into the fifo, the program reads the input as a list
 of URL's and creates some new easy handles to fetch each URL via the
 curl_multi "hiper" API.
 
-
 Thus, you can try a single URL:
   % echo http://www.yahoo.com > hiper.fifo
 

docs/examples/evhiperfifo.c

@@ -44,7 +44,6 @@ Whenever there is input into the fifo, the program reads the input as a list
 of URL's and creates some new easy handles to fetch each URL via the
 curl_multi "hiper" API.
 
-
 Thus, you can try a single URL:
   % echo http://www.yahoo.com > hiper.fifo
 

docs/examples/ghiper.c

@@ -41,7 +41,6 @@
  of URL's and creates some new easy handles to fetch each URL via the
  curl_multi "hiper" API.
 
-
  Thus, you can try a single URL:
  % echo http://www.yahoo.com > hiper.fifo
 

docs/examples/hiperfifo.c

@@ -41,7 +41,6 @@ Whenever there is input into the fifo, the program reads the input as a list
 of URL's and creates some new easy handles to fetch each URL via the
 curl_multi "hiper" API.
 
-
 Thus, you can try a single URL:
   % echo http://www.yahoo.com > hiper.fifo
 

docs/examples/htmltitle.cpp

@@ -46,9 +46,9 @@
 //
 
 #ifdef _WIN32
-#define COMPARE(a, b) (!_stricmp((a), (b)))
+#define COMPARE(a, b) (!_stricmp(a, b))
 #else
-#define COMPARE(a, b) (!strcasecmp((a), (b)))
+#define COMPARE(a, b) (!strcasecmp(a, b))
 #endif
 
 //

docs/examples/http2-upload.c

@@ -67,7 +67,7 @@
 #endif
 
 #ifdef _MSC_VER
-#define gettimeofday(a, b) my_gettimeofday((a), (b))
+#define gettimeofday(a, b) my_gettimeofday(a, b)
 static int my_gettimeofday(struct timeval *tp, void *tzp)
 {
   (void)tzp;

docs/examples/postit2-formadd.c

@@ -74,7 +74,6 @@ int main(int argc, char *argv[])
                  CURLFORM_COPYCONTENTS, "postit2-formadd.c",
                  CURLFORM_END);
 
-
     /* Fill in the submit field too, even if this is rarely needed */
     curl_formadd(&formpost,
                  &lastptr,

docs/libcurl/curl_easy_getinfo.md

@@ -398,7 +398,6 @@ An overview of the time values available from curl_easy_getinfo(3)
         |--|--|--|--|--|--|--|--TOTAL
         |--|--|--|--|--|--|--|--REDIRECT
 
-
  CURLINFO_QUEUE_TIME_T(3), CURLINFO_NAMELOOKUP_TIME_T(3),
  CURLINFO_CONNECT_TIME_T(3), CURLINFO_APPCONNECT_TIME_T(3),
  CURLINFO_PRETRANSFER_TIME_T(3), CURLINFO_POSTTRANSFER_TIME_T(3),