HID: intel-ish-hid: initialize ts_format.reserved

ts_format.reserved is not used anywhere yet, but the compiler generates a
warning when the struct's (uninitialized) field is being copied around

drivers/hid/intel-ish-hid/ipc/ipc.c: In function ‘write_ipc_from_queue’:
drivers/hid/intel-ish-hid/ipc/ipc.c:316: warning: ‘ts_format.reserved’ may be used uninitialized in this function

Avoid this by force-initializing the field to zero.
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/intel-ish-hid/ipc/ipc.c

@@ -310,6 +310,7 @@ static int write_ipc_from_queue(struct ishtp_device *dev)
 						((uint32_t)tv_utc.tv_usec);
 		ts_format.ts1_source = HOST_SYSTEM_TIME_USEC;
 		ts_format.ts2_source = HOST_UTC_TIME_USEC;
+		ts_format.reserved = 0;
 
 		time_update.primary_host_time = usec_system;
 		time_update.secondary_host_time = usec_utc;