cxgbe t4_tls: Call t4_rcvd_locked from do_rx_tls_cmp

Similar to dcfddc8dc091e7688abc8488a0307eba425fa7a2, replace the
simpler, inlined version with the full version.

Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D41690

(cherry picked from commit 897e564361624411c4e557e0817642e1477f0af4)