qemu-iotests: add support for Archipelago protocol

Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

tests/qemu-iotests/common

@@ -152,6 +152,7 @@ check options
     -nbd                test nbd
     -ssh                test ssh
     -nfs                test nfs
+    -archipelago        test archipelago
     -xdiff              graphical mode diff
     -nocache            use O_DIRECT on backing file
     -misalign           misalign memory allocations
@@ -263,6 +264,11 @@ testlist options
             xpand=false
             ;;
 
+        -archipelago)
+            IMGPROTO=archipelago
+            xpand=false
+            ;;
+
         -nocache)
             CACHEMODE="none"
             CACHEMODE_IS_DEFAULT=false