[media] saa7134: change the debug macros for IR input

Rename the macros to input_dbg() and ir_dbg(), using pr_fmt()
on both, to be coherent with the other debug macro changes.

The ir_dbg() also prints the IR name.

I'm not sure if it is a good idea to keep both macros here,
but merging them would require tests on different flavors of
saaa7134-based boards.

So, for now, let's keep both.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>