tests: allow to specify list of formats to test for check-block.sh

This would make code better and allow to test specific format.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

tests/check-block.sh

 #!/bin/sh
 
+FORMAT_LIST="raw qcow2 qed vmdk vpc"
+if [ "$#" -ne 0 ]; then
+    FORMAT_LIST="$@"
+fi
+
 export QEMU_PROG="$(pwd)/x86_64-softmmu/qemu-system-x86_64"
 export QEMU_IMG_PROG="$(pwd)/qemu-img"
 export QEMU_IO_PROG="$(pwd)/qemu-io"
@@ -12,10 +17,8 @@ fi
 cd tests/qemu-iotests
 
 ret=0
-./check -T -nocache -raw || ret=1
-./check -T -nocache -qcow2 || ret=1
-./check -T -nocache -qed|| ret=1
-./check -T -nocache -vmdk|| ret=1
-./check -T -nocache -vpc || ret=1
+for FMT in $FORMAT_LIST ; do
+    ./check -T -nocache -$FMT || ret=1
+done
 
 exit $ret