HID: pidff: Fix condition effect bit clearing

HID: pidff: Fix condition effect bit clearing

As reported by MPDarkGuy on discord, NULL pointer dereferences were
happening because not all the conditional effects bits were cleared.

Properly clear all conditional effect bits from ffbit

Fixes: 7f3d7bc0df4b ("HID: pidff: Better quirk assigment when searching for fields")
Cc: stable@vger.kernel.org # 6.18.x
Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>