core: fix search of SDs when filtered by host

Following change-id: I862873171c6753f8c8863c10c336e981e39dc8cb,
searching storage domains by an host looks like [1].
I.e. the left outer join is being made on the storage_pool_id;
which leads to multiple records of the same storage domain
(since a data-center can contain multiple hosts).

Therefore, reverted to previous search so it looks like [2].
I.e. the join is being made on the storage domain id,
hence, ensuring a distinct result set.

Similarly, it is mandatory to revert the opposite search
(hosts by storage domain) to use 'vds_with_tags' view again.

Fixed relevant tests in SyntaxCheckerTest.

[1]
SELECT storage_domains_for_search.* FROM storage_domains_for_search
LEFT OUTER JOIN vds_with_tags ON
storage_domains_for_search.storage_pool_id=vds_with_tags.storage_pool_id
WHERE  vds_with_tags.vds_name ILIKE 'host1')
ORDER BY storage_name ASC

[2]
SELECT storage_domains_for_search.* FROM storage_domains_for_search
LEFT OUTER JOIN vds_with_tags ON
storage_domains_for_search.id=vds_with_tags.storage_id
WHERE  vds_with_tags.vds_name ILIKE 'host1')
ORDER BY storage_name ASC

Change-Id: I04e37501b29a17a634e31e8875d63577e5f9f401
Bug-Url: https://bugzilla.redhat.com/1113891
Signed-off-by: Daniel Erez <derez@redhat.com>