kernel/ptrace.c should #include <linux/syscalls.h>

Every file should include the headers containing the prototypes for its global
functions (in this case sys_ptrace()).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 74730e0..628b03a 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -20,6 +20,7 @@
 #include <linux/signal.h>
 #include <linux/audit.h>
 #include <linux/pid_namespace.h>
+#include <linux/syscalls.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>