lapd/test: Extend test case to test msgs having data before l2h

Since e.g. the IPA input driver leaves it's specific header in front
of msg->l2h, so that msg->l2h != msg->data. The lapdm code does not expect this at least in
rslms_rx_rll_est_req().

This patch modifies the test program to add a dummy L1 header to
generated messages (unless the test would abort when doing so).

Note that the ok file reflects the current state which is not
correct.

Sponsored-by: On-Waves ehf
2 files changed