HID: intel-ish-hid: add MODULE_DESCRIPTION()

Fix the 'make W=1' warning:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/intel-ish-hid/intel-ishtp.o

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>