staging: vt6655: fix sparse warning: argument type

Fixes following warning generated by sparse:

drivers/staging/vt6655/baseband.c:2180:45: warning: incorrect type in argument 1 (different address spaces)
drivers/staging/vt6655/baseband.c:2180:45:    expected struct vnt_private *priv
drivers/staging/vt6655/baseband.c:2180:45:    got void [noderef] <asn:2>*dwIoBase

Compile tested on next-20141219.

Signed-off-by: Eddie Kovsky <ewk@edkovsky.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>