V4L/DVB (7465): Fix eeprom parsing and errors on the HVR1800 products

On some models, the valid Hauppauge eeprom data begins at a different offset.
This patch avoid unfriendly 'corrupt' eeprom errors during driver load.

Signed-off-by: Steven Toth <stoth@hauppauge.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>