powerpc: Fix ABIv2 issues with stack offsets in assembly code

Fix STK_PARAM and use it instead of hardcoding ABIv1 offsets.

Signed-off-by: Anton Blanchard <anton@samba.org>

diff --cc arch/powerpc/include/asm/ppc_asm.h
Simple merge

diff --cc arch/powerpc/lib/copypage_power7.S
Simple merge

diff --cc arch/powerpc/lib/copyuser_power7.S
Simple merge

diff --cc arch/powerpc/lib/memcpy_64.S
Simple merge

diff --cc arch/powerpc/lib/memcpy_power7.S
Simple merge