[media] lmedm04: make lme2510_powerup a little smaller

gcc isn't smart enough to realize it can share most of the argument
buildup and the actual function call between the two branches, so help
it a little.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>