docs: spelling nits

- MingW -> MinGW (Minimalist GNU for Windows)
- f.e. -> e.g.
- some whitespace and punctuation.

Reviewed-by: Daniel Stenberg

Closes #9622

docs/FAQ

@@ -1209,7 +1209,7 @@ FAQ
 
        Target:          static lib.   import lib for libcurl*.dll.
        -----------------------------------------------------------
-       MingW:           libcurl.a     libcurldll.a
+       MinGW:           libcurl.a     libcurldll.a
        MSVC (release):  libcurl.lib   libcurl_imp.lib
        MSVC (debug):    libcurld.lib  libcurld_imp.lib
        Borland:         libcurl.lib   libcurl_imp.lib

docs/INSTALL.md

@@ -149,9 +149,9 @@ multi-threaded dynamic C runtime.
 
  If you get linkage errors read section 5.7 of the FAQ document.
 
-## MingW32
+## MinGW32
 
-Make sure that MingW32's bin directory is in the search path, for example:
+Make sure that MinGW32's bin directory is in the search path, for example:
 
 ```cmd
 set PATH=c:\mingw32\bin;%PATH%

docs/examples/Makefile.m32

@@ -24,14 +24,14 @@
 
 ###########################################################################
 #
-## Makefile for building curl examples with MingW (GCC-3.2 or later)
+## Makefile for building curl examples with MinGW (GCC-3.2 or later)
 ## and optionally OpenSSL (1.0.2a), libssh2 (1.5), zlib (1.2.8), librtmp (2.4),
 ## brotli (1.0.1), zstd (1.4.5)
 ##
 ## Usage:   mingw32-make -f Makefile.m32 CFG=-feature1[-feature2][-feature3][...]
 ## Example: mingw32-make -f Makefile.m32 CFG=-zlib-ssl-sspi-winidn
 ##
-## Hint: you can also set environment vars to control the build, f.e.:
+## Hint: you can also set environment vars to control the build, e.g.:
 ## set ZLIB_PATH=c:/zlib-1.2.8
 ## set ZLIB=1
 #