PPC: Add asm helpers for BE 32bit load/store

From assembly code we might not only have to explicitly BE access 64bit values,
but sometimes also 32bit ones. Add helpers that allow for easy use of lwzx/stwx
in their respective byte-reverse or native form.
Signed-off-by: Alexander Graf <agraf@suse.de>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/asm-compat.h

@@ -34,10 +34,14 @@
 #define PPC_MIN_STKFRM	112
 
 #ifdef __BIG_ENDIAN__
+#define LWZX_BE	stringify_in_c(lwzx)
 #define LDX_BE	stringify_in_c(ldx)
+#define STWX_BE	stringify_in_c(stwx)
 #define STDX_BE	stringify_in_c(stdx)
 #else
+#define LWZX_BE	stringify_in_c(lwbrx)
 #define LDX_BE	stringify_in_c(ldbrx)
+#define STWX_BE	stringify_in_c(stwbrx)
 #define STDX_BE	stringify_in_c(stdbrx)
 #endif