common: Drop asm/ptrace.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/m68k/lib/traps.c b/arch/m68k/lib/traps.c
index 2ccd55a..c49141f 100644
--- a/arch/m68k/lib/traps.c
+++ b/arch/m68k/lib/traps.c
@@ -12,6 +12,7 @@
 #include <watchdog.h>
 #include <command.h>
 #include <asm/processor.h>
+#include <asm/ptrace.h>
 
 
 extern void _exc_handler(void);