target/ppc: Remove pp_check() and reuse ppc_hash32_pp_prot()

target/ppc: Remove pp_check() and reuse ppc_hash32_pp_prot()

The ppc_hash32_pp_prot() function in mmu-hash32.c is the same as
pp_check() in mmu_common.c, merge these to remove duplicated code.
Define the common function as static lnline otherwise exporting the
function from mmu-hash32.c would stop the compiler inlining it which
results in slightly lower performance.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
[np: move ppc_hash32_pp_prot inline without changing it]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>