Qt5CoreMacros: Sync with CMake project counterpart

Port of CMake commits:

commit 2622bc3f65162bf6d6cb5838da6999f8b5ca75cf
Author: Rolf Eike Beer <eike@sf-mail.de>
Date:   Sun Apr 6 21:30:00 2014 +0200

    Clean up usage of if(... MATCHES regex) followed string(REGEX REPLACE regex)

commit 7beba98652212c7a44f291b51dd03681e5193c49
Author: Robert Maynard <robert.maynard@kitware.com>
Date:   Thu Apr 3 11:27:58 2014 -0400

    Qt4Macros: Make QT4_CREATE_MOC_COMMAND a function

Change-Id: I5b928d114adb393ed9370163609311b7486e4a36
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

src/corelib/Qt5CoreMacros.cmake

@@ -53,8 +53,8 @@ macro(QT5_MAKE_OUTPUT_FILE infile prefix ext outfile )
     else()
         file(RELATIVE_PATH rel ${CMAKE_CURRENT_SOURCE_DIR} ${infile})
     endif()
-    if(WIN32 AND rel MATCHES "^[a-zA-Z]:") # absolute path
-        string(REGEX REPLACE "^([a-zA-Z]):(.*)$" "\\1_\\2" rel "${rel}")
+    if(WIN32 AND rel MATCHES "^([a-zA-Z]):(.*)$") # absolute path
+        set(rel "${CMAKE_MATCH_1}_${CMAKE_MATCH_2}")
     endif()
     set(_outfile "${CMAKE_CURRENT_BINARY_DIR}/${rel}")
     string(REPLACE ".." "__" _outfile ${_outfile})
@@ -94,7 +94,7 @@ endmacro()
 
 
 # helper macro to set up a moc rule
-macro(QT5_CREATE_MOC_COMMAND infile outfile moc_flags moc_options moc_target)
+function(QT5_CREATE_MOC_COMMAND infile outfile moc_flags moc_options moc_target)
     # Pass the parameters in a file.  Set the working directory to
     # be that containing the parameters file and reference it by
     # just the file name.  This is necessary because the moc tool on
@@ -134,7 +134,7 @@ macro(QT5_CREATE_MOC_COMMAND infile outfile moc_flags moc_options moc_target)
                        DEPENDS ${infile}
                        ${_moc_working_dir}
                        VERBATIM)
-endmacro()
+endfunction()
 
 
 function(QT5_GENERATE_MOC infile outfile )