In preparation to fix the alias issues on AIX, this patch changes
ASM_DECLARE_FUNCTION_NAME from a macro to a function.

Bootstrap on powerpc-ibm-aix7.1.0.0 in progress.

        * config/rs6000/xcoff.h (ASM_DECLARE_FUNCTION_NAME): Remove definition
        and call...
        * config/rs6000/rs6000.c (rs6000_xcoff_declare_function_name): New
        function.
        * config/rs6000/rs6000-protos.h (rs6000_xcoff_declare_function_name):
        Declare.


Thanks, David