[media] cx18: check for allocation failure in cx18_read_eeprom()

It upsets static checkers when we don't check for allocation failure.  I
moved the memset() of "tv" earlier so we don't use uninitialized data on
error.
Fixes: 1d212cf0c2d8 ('[media] cx18: struct i2c_client is too big for stack')

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Andy Walls <awalls@md.metrocast.net>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/pci/cx18/cx18-driver.c

@@ -327,13 +327,16 @@ void cx18_read_eeprom(struct cx18 *cx, struct tveeprom *tv)
 	struct i2c_client *c;
 	u8 eedata[256];
 
+	memset(tv, 0, sizeof(*tv));
+
 	c = kzalloc(sizeof(*c), GFP_KERNEL);
+	if (!c)
+		return;
 
 	strlcpy(c->name, "cx18 tveeprom tmp", sizeof(c->name));
 	c->adapter = &cx->i2c_adap[0];
 	c->addr = 0xa0 >> 1;
 
-	memset(tv, 0, sizeof(*tv));
 	if (tveeprom_read(c, eedata, sizeof(eedata)))
 		goto ret;