Staging: vt6656: Remove bogus parentheses in conditions

Removes unrequired parentheses around comparisons in complex
conditions.
Signed-off-by: Sebastian Rachuj <sebastian.rachuj@studium.uni-erlangen.de>
Signed-off-by: Simon Schuster <linux@rationality.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>