[media] pulse8-cec: avoid uninitialized data use

Building with -Wmaybe-uninitialized reveals the use on an uninitialized
variable containing the physical address of the device whenever
firmware before version 2 is used:

drivers/staging/media/pulse8-cec/pulse8-cec.c: In function 'pulse8_connect':
drivers/staging/media/pulse8-cec/pulse8-cec.c:447:2: error: 'pa' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This sets the address to CEC_PHYS_ADDR_INVALID in this case, so we don't
try to write back the uninitialized data to the device.

Fixes: e28a6c8b ("[media] pulse8-cec: sync configuration with adapter")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/staging/media/pulse8-cec/pulse8-cec.c

@@ -342,8 +342,10 @@ static int pulse8_setup(struct pulse8 *pulse8, struct serio *serio,
 		return err;
 	pulse8->vers = (data[0] << 8) | data[1];
 	dev_info(pulse8->dev, "Firmware version %04x\n", pulse8->vers);
-	if (pulse8->vers < 2)
+	if (pulse8->vers < 2) {
+		*pa = CEC_PHYS_ADDR_INVALID;
 		return 0;
+	}
 
 	cmd[0] = MSGCODE_GET_BUILDDATE;
 	err = pulse8_send_and_wait(pulse8, cmd, 1, cmd[0], 4);