ARM: davinci: dm644x: don't force vpfe registeration on all boards

Move all vpfe platform device registrations to the board specific
file.

This removes registration of vpfe platform devices on boards which
do not use vpfe.

Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>