Sanitize linker name to parse implicit link line (#14154)

Teach CMakeParseImplicitLinkInfo to convert the CMAKE_LINKER file name
to a regular expression that matches only the original name.  Escape
special characters like '+' so they are not treated as regex syntax.
Extend the ImplicitLinkInfoTest to test handling of a CMAKE_LINKER value
with many special characters.

Modules/CMakeParseImplicitLinkInfo.cmake

@@ -26,6 +26,7 @@ function(CMAKE_PARSE_IMPLICIT_LINK_INFO text lib_var dir_var fwk_var log_var obj
   set(linker "CMAKE_LINKER-NOTFOUND")
   if(CMAKE_LINKER)
     get_filename_component(linker ${CMAKE_LINKER} NAME)
+    string(REGEX REPLACE "([][+.*?()^$])" "\\\\\\1" linker "${linker}")
   endif()
   # Construct a regex to match linker lines.  It must match both the
   # whole line and just the command (argv[0]).

Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in

@@ -508,6 +508,7 @@ list(APPEND platforms msys_g77)
 
 #-----------------------------------------------------------------------------
 # Test parsing for all above examples.
+set(CMAKE_LINKER "not-a-linker[]().*+^$?")
 
 foreach(p IN LISTS platforms)
   cmake_parse_implicit_link_info("${${p}_text}" libs dirs fwks log "${${p}_obj_regex}")