V4L/DVB: tm6000: Replace all magic values by a register alias

Instead of using magic pairs of req/reg, replace them by the defined
values.

This patch were generated by the following script:

cat tm6000-regs.h |perl -ne 'if (m/(TM6010_REQ[^\s]+)\s+0x([a-f0-9]+)\,
0x([a-f0-9]+)/) { $name="$1"; $req=$2; $val=$3; printf
"s/REQ_${req}_SET_GET_AVREG[_BIT]*, 0x[0]*$3,/$1,/\n" }'  >a; for i in
tm*.c; do sed -f a $i >b && mv b $i; done

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>