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>

arch/parisc/hpux/gate.S

@@ -9,7 +9,7 @@
  */
 
 #include <asm/assembly.h>
-#include <asm/offsets.h>
+#include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 #include <asm/errno.h>