[media] include: lirc: add set length and frequency ioctl options

[media] include: lirc: add set length and frequency ioctl options

The Lirc framework works mainly with receivers, but there is
nothing that prevents us from using it for transmitters as well.

For that we need to have more control on the device frequency to
set (which is a new concept fro LIRC) and we also need to provide
to userspace, as feedback, the values of the used frequency and
length.

Add the LIRC_SET_LENGTH, LIRC_GET_FREQUENCY and
LIRC_SET_FREQUENCY ioctl commands in order to allow the above
mentioned operations.

Change-Id: I50b08e4da89a61f4b14f8a2752b905bc9e4a1d34
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>