[ARM] Remove needless linux/ptrace.h includes

Lots of places in arch/arm were needlessly including linux/ptrace.h,
resumably because we used to pass a struct pt_regs to interrupt
handlers.  Now that we don't, all these ptrace.h includes are
redundant.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/process.c

@@ -16,7 +16,6 @@
 #include <linux/mm.h>
 #include <linux/stddef.h>
 #include <linux/unistd.h>
-#include <linux/ptrace.h>
 #include <linux/slab.h>
 #include <linux/user.h>
 #include <linux/a.out.h>