bernard.xiong6db90b15affix the cortex-m3 context switch bug when interrupt preempts pendsv exception; add RT_LWIP_ETH_PAD_SIZE option; fix device activate flag set issue in init function.
6db90b15af
fix the cortex-m3 context switch bug when interrupt preempts pendsv exception; add RT_LWIP_ETH_PAD_SIZE option; fix device activate flag set issue in init function.