tests/qemu-iotests: Restrict test 114 to the 'file' protocol

tests/qemu-iotests: Restrict test 114 to the 'file' protocol

iotest 114 uses "truncate" and the qcow2.py script on the destination file,
which both cannot deal with URIs. Thus this test needs the "file" protocol,
otherwise it fails with an error message like this:

 truncate: cannot open 'ssh://127.0.0.1/tmp/qemu-build/tests/qemu-iotests/scratch/qcow2-ssh-114/t.qcow2.orig'
  for writing: No such file or directory

Thus mark this test for "file protocol only" accordingly.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20240315111108.153201-4-thuth@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>