powerpc: move ASM_CONST and stringify_in_c() into asm-const.h

This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/jump_label.h

@@ -14,7 +14,7 @@
 #include <linux/types.h>
 
 #include <asm/feature-fixups.h>
-#include <asm/asm-compat.h>
+#include <asm/asm-const.h>
 
 #define JUMP_ENTRY_TYPE		stringify_in_c(FTR_ENTRY_LONG)
 #define JUMP_LABEL_NOP_SIZE	4