Remove EXMIMO leftover

- Remove all files referencing EXMIMO
- Remove all targets/variables/defines that seem to be related to EXMIMO

openair2/LAYER2/RLC/UM_v9.3.0/rlc_um_segment.c

@@ -364,9 +364,6 @@ rlc_um_segment_10 (const protocol_ctxt_t* const ctxt_pP, rlc_um_entity_t *rlc_pP
               sdu_mngt_p->sdu_remaining_size,
               pdu_remaining_size - sdu_mngt_p->sdu_remaining_size);
 #endif
-//#if !EXMIMO
-//        assert(1!=1);
-//#endif
         memcpy(data, data_sdu_p, sdu_mngt_p->sdu_remaining_size);
         // reduce the size of the PDU
         continue_fill_pdu_with_sdu = 0;