migration: postcopy take proper error return

This function returns a boolean success and we're returning -1;
lets just use the 'out' error path.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: 58b7c17e ("Disable mlock around incoming postcopy")
Buglink: https://bugs.launchpad.net/qemu/+bug/1885720


Message-Id: <20200701093557.130096-1-dgilbert@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

migration/postcopy-ram.c

@@ -389,7 +389,7 @@ bool postcopy_ram_supported_by_host(MigrationIncomingState *mis)
      */
     if (munlockall()) {
         error_report("%s: munlockall: %s", __func__,  strerror(errno));
-        return -1;
+        goto out;
     }
 
     /*