staging: vt6656: limit reg output to block size

commit 69cc1f925e1aa74b96e2ace67e3453a50d091d2f upstream.

vnt_control_out appears to fail when BBREG is greater than 64 writes.

Create new function that will relay an array in no larger than
the indicated block size.

It appears that this command has always failed but was ignored by
driver until the introduction of error checking.

Cc: stable <stable@vger.kernel.org> # v5.3+
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Link: https://lore.kernel.org/r/a41f0601-df46-ce6e-ab7c-35e697946e2a@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>