[pvr] fix deleting recording folders

The underlying routines perform the recording info tag check so it's
not necessary to do it here at all. This is also why folders couldn't
be deleted earlier.

@xhaggi for sanity checking
if we are not permitted to remove this check please adjust it to
```
if (!item.IsPVRRecording() && !item.m_bIsFolder)
  return bReturn;
```