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/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S
index 74b1e90..a495657 100644
--- a/arch/xtensa/kernel/align.S
+++ b/arch/xtensa/kernel/align.S
@@ -19,7 +19,7 @@
 #include <asm/ptrace.h>
 #include <asm/ptrace.h>
 #include <asm/current.h>
-#include <asm/offsets.h>
+#include <asm/asm-offsets.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 #include <asm/page.h>