Input: synaptics-rmi4 - enable IRQ operation in F34 V7

The polled firmware update proved unreliable when testing on S7817. Use
attention to signal commands are complete.

Signed-off-by: Nick Dyer <nick@shmanahar.org>
Tested-by: Chris Healy <cphealy@gmail.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>