matchbox-lib: include setjmp.h

Based on this upstream patch:

   http://git.yoctoproject.org/cgit/cgit.cgi/libmatchbox/commit/?id=9315bcce1f01e7d6c00161442d61d3c676794d9d

Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
--- libmatchbox-1.9/libmb/mbpixbuf.c.orig	2014-02-21 12:45:46.867035956 +0000
+++ libmatchbox-1.9/libmb/mbpixbuf.c	2014-02-21 12:46:43.482949583 +0000
@@ -22,6 +22,7 @@
 
 #include <strings.h>
 #include "mbpixbuf.h"
+#include <setjmp.h>
 
 #define BYTE_ORD_24_RGB  0
 #define BYTE_ORD_24_RBG  1
