media: cec: set ev rather than v with CEC_PIN_EVENT_FL_DROPPED bit

Setting v with the CEC_PIN_EVENT_FL_DROPPED is incorrect, instead
ev should be set with this bit. Fix this.

Detected by CoverityScan, CID#1467974 ("Extra high-order bits")

Fixes: 6ec1cbf6 ("media: cec: improve CEC pin event handling")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>