AudioPlayback: source lib_video.sh to enable video_step

- Add `. "$TOOLS/lib_video.sh"` after audio_common sourcing.
- Fixes runtime error: `video_step: not found` on AudioPlayback runs.
- Reuses existing video helpers (e.g., video_step) for consistent logging.

Signed-off-by: Srikanth Muppandam <smuppand@qti.qualcomm.com>

Author: smuppand

Runner/suites/Multimedia/Audio/AudioPlayback/run.sh

@@ -38,6 +38,8 @@ fi
 . "$TOOLS/functestlib.sh"
 # shellcheck disable=SC1091
 . "$TOOLS/audio_common.sh"
+# shellcheck disable=SC1091
+. "$TOOLS/lib_video.sh"
 
 TESTNAME="AudioPlayback"
 RES_FILE="./${TESTNAME}.res"