[media] nuvoton-cir: simplify raw IR sample handling

The nuvoton-cir driver was storing up consecutive pulse-pulse and
space-space samples internally, for no good reason, since
ir_raw_event_store_with_filter() already merges back to back like
samples types for us. This should also fix a regression introduced late
in 3.0 that related to a timeout change, which actually becomes correct
when coupled with this change. Tested with RC6 and RC5 on my own
nuvoton-cir hardware atop vanilla 3.0.0, after verifying quirky
behavior in 3.0 due to the timeout change.

Reported-by: Stephan Raue <sraue@openelec.tv>
CC: Stephan Raue <sraue@openelec.tv>
CC: stable@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>