wpa: Fix a SIGBUS error in wpa_sm_set_rekey_offload
Incorrectly linked built-in wpa functions resulted in overwriting
sm->ctx->set_rekey_offload with garbage. It was initialized correctly
however it changed after wpa_supplicant became a daemon.
No SIGBUS violations reported by dhw@ were experienced during testing
of the original commit by msyelf or philip@.
Reported by: dhw
Tested by: dhw
X-MFC with: 25ecdc7d52770caf1c9b44b5ec11f468f6b636f3
(cherry picked from commit 9a0f82285322a338548d13fcda07e1d574301190)