touch: fts: add mutex to protect offload report When the release_all_touches and offload_report run at the same time, it may cause the input report conflict before input sync. bug: 190460965 Test: flash boot.img and vendor_boot.img. Signed-off-by: davidycchen <[email protected]> Change-Id: I35e5d296a762629e64d0851f5336b7de604f8e86