minigbm: fix size_t type not found

BUG=b:24674340
TEST=build pass on kevin

Change-Id: Idd780ee5e99e864ed0f97503e7b38673761201e8
Reviewed-on: https://chromium-review.googlesource.com/422808
Commit-Ready: Heng-ruey Hsu <henryhsu@chromium.org>
Tested-by: Heng-ruey Hsu <henryhsu@chromium.org>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/gbm.h b/gbm.h
index 839e2a5..03c10ec 100644
--- a/gbm.h
+++ b/gbm.h
@@ -35,6 +35,7 @@ extern "C" {
 
 #define __GBM__ 1
 
+#include <stddef.h>
 #include <stdint.h>
 
 /**