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/spear/timer.c b/arch/arm/cpu/arm926ejs/spear/timer.c
index 9db1c74..6803c34 100644
--- a/arch/arm/cpu/arm926ejs/spear/timer.c
+++ b/arch/arm/cpu/arm926ejs/spear/timer.c
@@ -11,6 +11,7 @@
 #include <asm/arch/hardware.h>
 #include <asm/arch/spr_gpt.h>
 #include <asm/arch/spr_misc.h>
+#include <asm/ptrace.h>
 
 #define GPT_RESOLUTION	(CONFIG_SPEAR_HZ_CLOCK / CONFIG_SPEAR_HZ)
 #define READ_TIMER()	(readl(&gpt_regs_p->count) & GPT_FREE_RUNNING)