[media] rtl28xxu: fix rtl2832u module reload fails bug

This is workaround / partial fix.

rtl2832u_power_ctrl() and rtl2832u_frontend_attach() needs to
be go through carefully and fix properly. There is clearly
some logical errors when handling power-management ang GPIOs...

Signed-off-by: Antti Palosaari <crope@iki.fi>
Cc: Thomas Mair <thomas.mair86@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>