staging: bcm: Cleanup unneeded boolean comparisons

Cleans up a few needless comparisons with booleans and cleans up an
interupt handler to take advantage of earlier bailout shortcircuit.

Signed-off-by: Jade Bilkey <herself@thefumon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>