av1_cx_iface.c: add missing setjmp include

Change-Id: Ifcc5695b96b67854bd20987baf94863bb0269123

av1/av1_cx_iface.c

diff --git a/av1/av1_cx_iface.c b/av1/av1_cx_iface.c
index 69140cc..00c6147 100644
--- a/av1/av1_cx_iface.c
+++ b/av1/av1_cx_iface.c
@@ -12,6 +12,7 @@
 #include <assert.h>
 #include <limits.h>
 #include <math.h>
+#include <setjmp.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>