media: hdpvr: fix smatch warning

drivers/media/usb/hdpvr/hdpvr-i2c.c: drivers/media/usb/hdpvr/hdpvr-i2c.c:78 hdpvr_i2c_read() warn: 'dev->i2c_buf' 4216624615462223872 can't fit into 127 '*data'

dev->i2c_buf is a char array, so you can just use dev->i2c_buf to get the
start address, no need to do &dev->i2c_buf, even though it is the same
address in C. It only confuses smatch.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>