[qca-nss-clients] Allocate TCF block only for an IFB device.

TCF block is used for storing the filter list and currently
filter list is only allowed over an IFB device.

Signed-off-by: Manish Verma <maniverm@codeaurora.org>
Change-Id: I64cc0c5790ac9f380d571ea3b924acfb3db92359
1 file changed