tests: avoid more hard-coded CRLFs in protocol sections

- fix regex to not catch CR (from CRLF), in `PORT`, `EPRT`
  commands, allowing to use `crlf="yes"` more.
- add `crlf="headers"` mode for `protocol` sections.
  To call `subnewlines()` without its force option.
  This is the mode used in `data` sections when `crlf="yes"`.
  (This confusion may be subject to a future commit.)
- subnewlines: apply CRLF to `HEAD` and `CONNECT` HTTP requests.
- subnewlines: apply CRLF to RTSP requests.
- delete remaining empty `protocol` sections.

Reducing the number of `tests/data/test*`:
- CRLF newlines from 11325 to 10295. (119984 lines total)
- files with mixed newlines from 707 to 656. (1890 files total)

Follow-up to 4d2a05d3fe #19284

Closes #19318

tests/data/test577

@@ -39,12 +39,12 @@ rtsp://%HOSTIP:%RTSPPORT/%TESTNUMBER
 </client>
 
 <verify>
-<protocol>
-OPTIONS rtsp://%HOSTIP:%RTSPPORT/%TESTNUMBER RTSP/1.0
-CSeq: 1
-User-Agent: test567
-Test-Number: 567
-
+<protocol crlf="yes">
+OPTIONS rtsp://%HOSTIP:%RTSPPORT/%TESTNUMBER RTSP/1.0
+CSeq: 1
+User-Agent: test567
+Test-Number: 567
+
 </protocol>
 # 8 == CURLE_WEIRD_SERVER_REPLY
 <errorcode>