Release locked buffer when it fails to acquire graphics buffer

The JNI buffer in ImageReader_imageSetup is not released when
it fails to acquire graphics buffer. After all JNI buffers are
exhausted, ACQUIRE_MAX_IMAGES will be returned and leads to
error. The JNI buffer should be released when it fails to acquire
graphics buffer.

Change-Id: I3319a58ac44e36c8593b404672a685c4b589a735
diff --git a/media/jni/android_media_ImageReader.cpp b/media/jni/android_media_ImageReader.cpp
index 0030dbd..d475eee 100644
--- a/media/jni/android_media_ImageReader.cpp
+++ b/media/jni/android_media_ImageReader.cpp
@@ -707,6 +707,7 @@
     }
     status_t res = consumer->lockNextBuffer(buffer);
     if (res != NO_ERROR) {
+        ctx->returnLockedBuffer(buffer);
         if (res != BAD_VALUE /*no buffers*/) {
             if (res == NOT_ENOUGH_DATA) {
                 return ACQUIRE_MAX_IMAGES;