cmake: match filename suffixes with file content

To:
- simplify recognizing CMake sources.
- ensure syntax highlighters use the correct file type.
- sync .h template filename with its autotools counterpart.

Also:
- cmakelint.sh: simplify, alpha sort the filelist.
- perlcheck.sh: simplify.

Closes #20039

lib/CMakeLists.txt

@@ -26,7 +26,7 @@ set(LIBCURL_OUTPUT_NAME "${LIB_NAME}" CACHE STRING "Basename of the curl library
 
 set_property(DIRECTORY APPEND PROPERTY COMPILE_DEFINITIONS ${CURL_DEBUG_MACROS} "BUILDING_LIBCURL")
 
-configure_file("curl_config.h.cmake" "${CMAKE_CURRENT_BINARY_DIR}/curl_config.h")
+configure_file("curl_config-cmake.h.in" "${CMAKE_CURRENT_BINARY_DIR}/curl_config.h")
 
 # Get CSOURCES, HHEADERS, LIB_RCFILES variables
 curl_transform_makefile_inc("Makefile.inc" "${CMAKE_CURRENT_BINARY_DIR}/Makefile.inc.cmake")

lib/Makefile.am

@@ -26,7 +26,7 @@ AUTOMAKE_OPTIONS = foreign nostdinc
 # Get CSOURCES, HHEADERS, LIB_RCFILES variables
 include Makefile.inc
 
-CMAKE_DIST = CMakeLists.txt curl_config.h.cmake
+CMAKE_DIST = CMakeLists.txt curl_config-cmake.h.in
 
 EXTRA_DIST = config-mac.h config-os400.h config-plan9.h config-riscos.h \
   config-win32.h curl_config.h.in $(LIB_RCFILES) libcurl.def            \