HACK: fix regulator assignment for beagle x15

Ideally we would find a way to differentiate
between j6 evm and beagle x15, so we can get
proper regulator assignment for any of them.

Until then, on this branch at least, we will
make sure it's safe to use beagle x15.

Signed-off-by: Felipe Balbi <balbi@ti.com>
HACK: revert part of original

now that regulator assingment is correct, we
can enable IVA voltage scaling.

Signed-off-by: Felipe Balbi <balbi@ti.com>