V4L/DVB: dst: fixes for DVB-C Twinhan VP2031

V4L/DVB: dst: fixes for DVB-C Twinhan VP2031

Remove check  "state->dst_type == DST_DTYPE_IS_CABLE"  in function
dst_get_tuna (around line 1352) to select the correct checksum
computation

Fill in the .caps field in struct dst_dvbc_ops (around line 1824) with
all the supported QAM modulation methods to match the capabilities of
the card as implemented in function dst_set_modulation (around line
502). Note that beginning with linux kernel version 2.6.32 the
modulation method is checked (by function
dvb_frontend_check_parameters in file
drivers/media/dvb/dvb-core/dvb_frontend.c) and thus tuning fails if
you use a modulation method that is not present in the .caps field.

This patch has been tested on a Twinhan VP2031A DVB-C card with the
2.6.32.2 kernel.

Signed-off-by: Klaas de Waal <klaas.de.waal@gmail.com>
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>