Some callers (e.g. cmd/fs.c) of fs_set_blk_dev may use a NULL dev_part_str.
While blk_get_device_part_str handles this fine,
part_get_info_by_dev_and_name does not. This fixes commands crashing when
implicitly using bootdevice.
The unit test has also been updated to set bootdevice to a known value and
to restore it after we are done.
Fixes: 7194527b6a ("cmd: fs: Use part_get_info_by_dev_and_name_or_num to parse partitions")
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This is technically a library function, but we use MMCs for testing, so
it is easier to do it with DM. At the moment, the only block devices in
sandbox are MMCs (AFAIK) so we just test with those.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
