Implementation of unified EMAC driver for Renesas mbed boards
Based on the driver so far, Renesas implemented the emac driver for GR-PEACH and VK-RZ/A1H.
The mainly changes is below.
- Add the connection part with LWIP according to the unified emac specification.
- Add three new multicast functions(add, remove, set_all).
The Greentea test netsocket and emac test passed.