Staging: bcm: Queue.h: fix checkpatch errors: comments

This patch improves coding style in Queue.h
Comments according to the coding guideline

Signed-off-by: Martin Gumbrecht <martin.gumbrecht@googlemail.com>
Signed-off-by: Christian Bay <christian.bay@studium.fau.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>