lib: rename curlx_strtoofft to Curl_str_numblanks()

The function is no longer used via the curlx shortcut.

Remove the strtoofft.[ch] files.

Closes #16642

src/Makefile.inc

@@ -41,7 +41,6 @@ CURLX_CFILES = \
   ../lib/curl_multibyte.c \
   ../lib/dynbuf.c \
   ../lib/nonblock.c \
-  ../lib/strtoofft.c \
   ../lib/strparse.c \
   ../lib/strcase.c \
   ../lib/timediff.c \
@@ -54,7 +53,6 @@ CURLX_HFILES = \
   ../lib/curl_setup.h \
   ../lib/dynbuf.h \
   ../lib/nonblock.h \
-  ../lib/strtoofft.h \
   ../lib/strparse.h \
   ../lib/strcase.h \
   ../lib/timediff.h \

src/terminal.c

@@ -28,7 +28,7 @@
 #endif
 
 #include "terminal.h"
-#include "strtoofft.h"
+#include "curlx.h"
 
 #include "memdebug.h" /* keep this as LAST include */