m68k: merge per-CPU config.mk into arch/m68k/Makefile

Collect CPU specific flags into the single place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alison Wang <alison.wang@freescale.com>
Cc: Angelo Dureghello <angelo@sysam.it>
8 files changed