HID: rmi: Print the firmware id of the touchpad

Knowing the firmware id is extremely useful when debugging issues related to
the touchpad. It can be used to determine the hardware, firmware version,
and configuation of the touchpad. This patch queries the firmware id and
prints it as the touchpad is starting so that it will show up in the dmesg
output included in bug reports.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>