[media] msi3101: init bits 23:20 on PLL register

It is not sure what is meaning of that number, but it is better
to try do as Windows driver. It seems to have small effect for
signal when looking FM FFT.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>