Add missing end braces for extern C flag

Change-Id: I9d1eb3f2275defeecccde167cf835db77e9fb2c4
diff --git a/av1/encoder/intra_mode_search.h b/av1/encoder/intra_mode_search.h
index 23d5d10..a08c0a9 100644
--- a/av1/encoder/intra_mode_search.h
+++ b/av1/encoder/intra_mode_search.h
@@ -237,4 +237,8 @@
 // Resets palette color map for chroma channels.
 void av1_restore_uv_color_map(const AV1_COMP *const cpi, MACROBLOCK *x);
 
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
 #endif  // AOM_AV1_ENCODER_INTRA_MODE_SEARCH_H_