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/arm/cpu/arm926ejs/mx25/timer.c b/arch/arm/cpu/arm926ejs/mx25/timer.c
index 7e2698b..4b726d5 100644
--- a/arch/arm/cpu/arm926ejs/mx25/timer.c
+++ b/arch/arm/cpu/arm926ejs/mx25/timer.c
@@ -23,6 +23,7 @@
 #include <init.h>
 #include <asm/io.h>
 #include <asm/arch/imx-regs.h>
+#include <asm/ptrace.h>
 
 /* nothing really to do with interrupts, just starts up a counter. */
 /* The 32KHz 32-bit timer overruns in 134217 seconds */