V4L/DVB (5446): Renamed ASUStek P7131 card [1043:4876]

The new name fits to what it is and what is on the box.

Signed-off-by: Hartmut Hackmann <hartmut.hackmann@t-online.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>