qga-win: add support for qmp_guest_fsfreeze_freeze_list

This patch add support for freeze specified fs.

The valid mountpoints list member are [1]:

  The path of a mounted folder, for example, Y:\MountX\
  A drive letter, for example, D:\
  A volume GUID path of the form \\?\Volume{GUID}\,
      where GUID identifies the volume
  A UNC path that specifies a remote file share,
      for example, \\Clusterx\Share1\

[1] https://docs.microsoft.com/en-us/windows/desktop/api/vsbackup/nf-vsbackup-ivssbackupcomponents-addtosnapshotset

Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
diff --git a/qga/vss-win32.c b/qga/vss-win32.c
index a541f3a..f444a25 100644
--- a/qga/vss-win32.c
+++ b/qga/vss-win32.c
@@ -147,7 +147,8 @@
 }
 
 /* Call VSS requester and freeze/thaw filesystems and applications */
-void qga_vss_fsfreeze(int *nr_volume, bool freeze, Error **errp)
+void qga_vss_fsfreeze(int *nr_volume, bool freeze,
+                      strList *mountpoints, Error **errp)
 {
     const char *func_name = freeze ? "requester_freeze" : "requester_thaw";
     QGAVSSRequesterFunc func;
@@ -164,5 +165,5 @@
         return;
     }
 
-    func(nr_volume, &errset);
+    func(nr_volume, mountpoints, &errset);
 }