Allow for warning-free passing of -Wl options on config command line. One

possible usage is to pass -Wl,-z,-noexecstack on Linux to ensure the stack
is marked non-executable. Well, -Wa,--noexecstack works fine too...

Configure

@@ -724,7 +724,7 @@ PROCESS_ARGS:
 			}
 		elsif (/^[-+]/)
 			{
-			if (/^-[lL](.*)$/)
+			if (/^-[lL](.*)$/ or /^-Wl,/)
 				{
 				$libs.=$_." ";
 				}