Revert "Input: cros_ec_keyb - add back missing mask for event_type"

This reverts commit 62c38016.

This patch is not needed anymore since we clear EC_MKBP_HAS_MORE_EVENTS
flag before calling the notifiers in patch
"9d9518f5b52a (platform: chrome: cros_ec: handle MKBP more events flag)"

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>