powerpc, 8xx: move get_immr() into C

Avoid unnecessary assembly functions when they can easily be written
in C.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
diff --git a/arch/powerpc/include/asm/ppc.h b/arch/powerpc/include/asm/ppc.h
index 27d3b83..e11f398 100644
--- a/arch/powerpc/include/asm/ppc.h
+++ b/arch/powerpc/include/asm/ppc.h
@@ -38,8 +38,15 @@
 #include <asm/arch/immap_lsch2.h>
 #endif
 
+#include <asm/processor.h>
+
 #if defined(CONFIG_8xx)
-uint get_immr(uint);
+static inline uint get_immr(uint mask)
+{
+	uint immr = mfspr(SPRN_IMMR);
+
+	return mask ? (immr & mask) : immr;
+}
 #endif
 uint get_pvr(void);
 uint get_svr(void);