qemu-iotests: Filter out 'qemu-io> ' prompt

This removes "qemu-io> " prompt from qemu-io output in _filter_qemu_io,
and updates all the output files with the following command:

 cd tests/qemu-iotests && sed -i "s/qemu-io> //g" *.out

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/tests/qemu-iotests/025.out b/tests/qemu-iotests/025.out
index d245727..8c695e6 100644
--- a/tests/qemu-iotests/025.out
+++ b/tests/qemu-iotests/025.out
@@ -5,23 +5,23 @@
 
 === Writing whole image
 === IO: pattern 0xc5
-qemu-io> wrote 134217728/134217728 bytes at offset 0
+wrote 134217728/134217728 bytes at offset 0
 128 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-qemu-io> No errors were found on the image.
+No errors were found on the image.
 
 === Resizing image
-qemu-io> 128 MiB
-qemu-io> qemu-io> 384 MiB
-qemu-io> No errors were found on the image.
+128 MiB
+384 MiB
+No errors were found on the image.
 
 === Verifying image size after reopen
 384 MiB
 
 === Verifying resized image
 === IO: pattern 0xc5
-qemu-io> read 134217728/134217728 bytes at offset 0
+read 134217728/134217728 bytes at offset 0
 128 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-qemu-io> === IO: pattern 0
-qemu-io> read 268435456/268435456 bytes at offset 134217728
+=== IO: pattern 0
+read 268435456/268435456 bytes at offset 134217728
 256 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-qemu-io> *** done
+*** done