mm-video-v4l2: Disable low latency by default

Low latency is uninitialized in OMX right now.
Initialize it to be disabled.

CRs-Fixed: 2302120
Change-Id: I31a1f13a56fab2d090606641f0658720348abbe9
diff --git a/mm-video-v4l2/vidc/venc/src/video_encoder_device_v4l2.cpp b/mm-video-v4l2/vidc/venc/src/video_encoder_device_v4l2.cpp
index 00b32c9..2173b60 100644
--- a/mm-video-v4l2/vidc/venc/src/video_encoder_device_v4l2.cpp
+++ b/mm-video-v4l2/vidc/venc/src/video_encoder_device_v4l2.cpp
@@ -114,6 +114,7 @@
     mBatchSize = 0;
     deinterlace_enabled = false;
     m_roi_enabled = false;
+    low_latency_mode = false;
     pthread_mutex_init(&m_roilock, NULL);
     pthread_mutex_init(&pause_resume_mlock, NULL);
     pthread_cond_init(&pause_resume_cond, NULL);