[media] media: st-rc: Add ST remote control driver

This patch adds support to ST RC driver, which is basically a IR/UHF
receiver and transmitter. This IP (IRB) is common across all the ST
parts for settop box platforms. IRB is embedded in ST COMMS IP block.
It supports both Rx & Tx functionality.
This driver adds only Rx functionality via LIRC codec.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Acked-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>