cxgb4_uld_in_use() is used only by cxgb4_ktls_det_feature() which
is under CONFIG_CHELSIO_TLS_DEVICE macro.

Fixes: a3ac249a ("cxgb4/chcr: Enable ktls settings at run time")
Signed-off-by: Rohit Maheshwari <rohitm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>