STYLE: use a function instead of a macro, to keep FAIL_MESSAGE local

patch from Miguel

Alex

Modules/FindPackageHandleStandardArgs.cmake

@@ -17,7 +17,7 @@
 #    be "Could NOT find LibXml2", if you don't like this message you can specify
 #    your own custom failure message there.
 
-MACRO(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
+FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
 
   IF("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
     SET(_FAIL_MESSAGE "Could NOT find ${_NAME}")
@@ -32,6 +32,7 @@ MACRO(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
     SET(${_NAME_UPPER}_FOUND FALSE)
   ENDIF(NOT ${_VAR1})
 
+  # check if all passed variables are valid
   FOREACH(_CURRENT_VAR ${ARGN})
     IF(NOT ${_CURRENT_VAR})
       SET(${_NAME_UPPER}_FOUND FALSE)
@@ -51,4 +52,7 @@ MACRO(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
       ENDIF (NOT ${_NAME}_FIND_QUIETLY)
     ENDIF (${_NAME}_FIND_REQUIRED)
   ENDIF (${_NAME_UPPER}_FOUND)
-ENDMACRO(FIND_PACKAGE_HANDLE_STANDARD_ARGS)
+
+  SET(${_NAME_UPPER}_FOUND ${${_NAME_UPPER}_FOUND} PARENT_SCOPE)
+
+ENDFUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS)