HID: pidff: Fix needs_playback check

HID: pidff: Fix needs_playback check

A small bug made it's way here when rewriting code to Linux quality.
Currently, if an effect is not infinite and a program requests it's
playback with the same number of loops, the play command won't be fired
and if an effect is infinite, the spam will continue.

We want every playback update for non-infinite effects and only some
for infinite (detecting when a program requests stop with 0 which will
be different than previous value which is usually 1 or 255).

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>