drm/bochs: Remove unneeded semicolon

Fixes coccicheck warning:

drivers/gpu/drm/bochs/bochs_hw.c:258:2-3: Unneeded semicolon

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1576468459-67216-1-git-send-email-zhengbin13@huawei.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>