block: Handle bs->options in bdrv_open() only

block: Handle bs->options in bdrv_open() only

The fail paths of bdrv_file_open() and bdrv_open() naturally exhibit
similarities, thus it is possible to reuse the one from bdrv_open() and
shorten the one in bdrv_file_open() accordingly.

Also, setting bs->options in bdrv_file_open() is not necessary if it is
already done in bdrv_open().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>