* lib.rs: fix transmission status checking (line 176)
* lib.rs: make RAW_FRAME_LENGTH_MAX the same for both RX and TX, for the purpose of setting MAMXFL in controller, as well as setting MTU for smoltcp device
* smoltcp_phy.rs: fix missing MTU definition
* lib.rs: fix transmission status checking (line 176)
* lib.rs: make RAW_FRAME_LENGTH_MAX the same for both RX and TX, for the purpose of setting MAMXFL in controller, as well as setting MTU for smoltcp device
* smoltcp_phy.rs: fix missing MTU definition