dm space map metadata: fix sm_bootstrap_get_nr_blocks()
dm space map metadata: fix sm_bootstrap_get_nr_blocks()

This function isn't right and it causes a static checker warning:

	drivers/md/dm-thin.c:3016 maybe_resize_data_dev()
	error: potentially using uninitialized 'sb_data_size'.

It should set "*count" and return zero on success the same as the
sm_metadata_get_nr_blocks() function does earlier.

Fixes: 3241b1d3e0aa ('dm: add persistent data library')
Signed-off-by: Dan Carpenter <ff341aa343d564f9e53e9dcb6996be8c04859a66@oracle.com>
Acked-by: Joe Thornber <61d5fad70554ae22d57a37634e04f12f58acc678@redhat.com>
Signed-off-by: Mike Snitzer <85e533f2e78486213c4d69f71462342ec0c62734@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs