There are only two definitions from ethernet.h used in the driver.
Namely:
Both are only used in the file core/rtw_recv.c. Replace the usage of
ETHERNET_HEADER_SIZE with ETH_HLEN, move the definition of LLC_HEADER_SIZE
into rtw_recv.h and remove the now unused ethernet.h header file.
Link: https://lore.kernel.org/r/20210824123621.10801-4-straube.linux@gmail.com