vds_info: fixed gateway config handling

Previously the gateway configuration was dropped due
to a mistake in parsing the vds capabilities.
This patch fixes that parsing.

Change-Id: I57cabd5e317bd53cc597cf17fb8e2f9c4139712c
Bug-Url: https://bugzilla.redhat.com/1147254
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>