MIPS: unify cache maintenance functions

Move the more developed mips32 version of the cache maintenance
functions to a common arch/mips/lib/cache.c, in order to reduce
duplication between mips32 & mips64.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
4 files changed