iotests: Restrict nbd Python tests to nbd

We have two Python unittest-style tests that test NBD.  As such, they
should specify supported_protocols=['nbd'] so they are skipped when the
user wants to test some other protocol.

Furthermore, we should restrict their choice of formats to 'raw'.  The
idea of a protocol/format combination is to use some format over some
protocol; but we always use the raw format over NBD.  It does not really
matter what the NBD server uses on its end, and it is not a useful test
of the respective format driver anyway.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 7c932a1d69)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

tests/qemu-iotests/147

@@ -287,6 +287,5 @@ class BuiltinNBD(NBDBlockdevAddBase):
 
 
 if __name__ == '__main__':
-    # Need to support image creation
-    iotests.main(supported_fmts=['vpc', 'parallels', 'qcow', 'vdi', 'qcow2',
-                                 'vmdk', 'raw', 'vhdx', 'qed'])
+    iotests.main(supported_fmts=['raw'],
+                 supported_protocols=['nbd'])

tests/qemu-iotests/205

@@ -153,4 +153,5 @@ class TestNbdServerRemove(iotests.QMPTestCase):
 
 
 if __name__ == '__main__':
-    iotests.main(supported_fmts=['generic'])
+    iotests.main(supported_fmts=['raw'],
+                 supported_protocols=['nbd'])