common: Drop asm_offsets.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
index 40cb24d..c519e8b 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu_init_early.c
@@ -4,6 +4,7 @@
  */
 
 #include <common.h>
+#include <asm-offsets.h>
 #include <asm/processor.h>
 #include <asm/mmu.h>
 #include <asm/fsl_law.h>