Undef before redefining macros

-Werror,-Wmacro-redefined was turned on because of -Werror, -Wall.
Undefine the overridden macros before redefining them to let compiler
know that the redifinition is intentional.

Test: m -j sh_vendor

Change-Id: If324124e4504f05a37afd1021cff179fdfe4c08e
1 file changed