camera_metadata: cleanup dependency

camera_metadata doesn't depend on vendor tag header.

Bug: 30985004
Change-Id: Ib8939220801498a4427072b78efede7b08a7ffd3
diff --git a/camera/include/system/camera_metadata.h b/camera/include/system/camera_metadata.h
index 9de902b..4e322bd 100644
--- a/camera/include/system/camera_metadata.h
+++ b/camera/include/system/camera_metadata.h
@@ -20,7 +20,6 @@
 #include <string.h>
 #include <stdint.h>
 #include <cutils/compiler.h>
-#include <system/camera_vendor_tags.h>
 
 #ifdef __cplusplus
 extern "C" {