qga-win: Fix Event Viewer errors caused by qemu-ga

When the command "guest-fsfreeze-freeze" is executed it causes
the VSS service to log the error below in the Event Viewer. This
error is caused by an issue in the function "CommitSnapshots" in
provider.cpp:

* When VSS_TIMEOUT_MSEC expires the funtion returns E_ABORT. This causes
the error #12293.

|event id|                           error                               |
* 12293  : Volume Shadow Copy Service error: Error calling a routine on a
           Shadow Copy Provider {00000000-0000-0000-0000-000000000000}.
           Routine details CommitSnapshots [hr = 0x80004004, Operation
           aborted.

Signed-off-by: Sameeh Jubran <sameeh@daynix.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

qga/vss-win32/provider.cpp

@@ -377,7 +377,6 @@ STDMETHODIMP CQGAVssProvider::CommitSnapshots(VSS_ID SnapshotSetId)
     if (WaitForSingleObject(hEventThaw, VSS_TIMEOUT_MSEC) != WAIT_OBJECT_0) {
         /* Send event to qemu-ga to notify the provider is timed out */
         SetEvent(hEventTimeout);
-        hr = E_ABORT;
     }
 
     CloseHandle(hEventThaw);