Add gst1-bcm env vars to explora setup script

Author: krp97

board/explora/wpeframework.sh

@@ -18,6 +18,10 @@ export NF_GST_AUDIO_PCM_TRANSPORT_UNIT_OVERRIDE=5
 export NF_GST_AUDIO_PCM_LATENCY_OVERRIDE=170
 export NF_SW_PLAYBACK_QUEUE_SIZE_OVERRIDE=32
 export GST_DEBUG=1
+export GST_VIDEO_WINDOW_BOX_MODE='y'
+export GST_VIRTUAL_DISP_WIDTH=1280
+export GST_VIRTUAL_DISP_HEIGHT=720
+export GST_ENABLE_SVP='y'
 
 #FIXME: Temporary solution for TCP receive buffer size
 sysctl net.core.rmem_max=262144