[media] staging: lirc: remove sa1100 support

The LIRC support for sa1100 appears to have never worked
because it relies on header files that have never been
present in git history. Actually trying to build the
driver on an ARM sa1100 kernel fails, so let's just remove
the broken support.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jarod Wilson <jarod@wilsonet.com>
Cc: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>