support key repeat with dib0700 ir receiver - (resend signed off)

This patch enables support for repeating last event when a key is holded down with dib0700 devices. It works with rc5 and nec remotes. It also fixes an annoying bug that floods kernel log with "Unknown key" messages after each keypress. This happened because the driver was not resetting infrared register after each poll so it kept polling last key even if nothing was being pressed. Fixing this, (calling rc_setup after each poll), permits to implement key repeat.

Signed-off-by Filippo Argiolas <filippo.argiolas at gmail.com>

I'm resending the patch because I didn't sign it off the first time. It's been a while since it's out, it has been tested and received many positive comments and no complaint. Please refer to my previous post for a complete description of the problem and how the patch fixes it. Hope everything is ok for inclusion :P
Thanks,

Cheers,
Filippo