V4L/DVB (13926): gspca - pac7302: Fix a random USB error.

When loading the register 0x49 of the page 3, the usb_control_msg() sometimes
fails with error -71 or -62.
This change skips loading the register 0x48.

Tested-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>