kbuild: m68k,parisc,ppc,ppc64,s390,xtensa use generic asm-offsets.h support

Delete obsoleted parts form arch makefiles and rename to asm-offsets.h

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/ppc/kernel/misc.S b/arch/ppc/kernel/misc.S
index ce71b4a..90d917d 100644
--- a/arch/ppc/kernel/misc.S
+++ b/arch/ppc/kernel/misc.S
@@ -23,7 +23,7 @@
 #include <asm/mmu.h>
 #include <asm/ppc_asm.h>
 #include <asm/thread_info.h>
-#include <asm/offsets.h>
+#include <asm/asm-offsets.h>
 
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