Staging: bcm: Remove unnecessary "do while" statement in, IOCTL_BCM_BUFFER_DOWNLOAD

This patch removes a superfluous "do while"
statement in IOCTL_BCM_BUFFER_DOWNLOAD.

Signed-off-by: Kevin McKinney <klmckinney1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>