restore zalloc() (lost with OOM debug commit, used by lwip/lwip2)
restore zalloc() (lost with OOM debug commit, used by lwip/lwip2)

lrmoreno007/Arduino,hallard/Arduino,wemos/Arduino,Lan-Hekary/Arduino,wemos/Arduino,wemos/Arduino,wemos/Arduino,wemos/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,Adam5Wu/Arduino,lrmoreno007/Arduino,hallard/Arduino,Lan-Hekary/Arduino,Lan-Hekary/Arduino,Adam5Wu/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,Adam5Wu/Arduino,esp8266/Arduino,esp8266/Arduino,lrmoreno007/Arduino,sticilface/Arduino,hallard/Arduino,esp8266/Arduino,sticilface/Arduino,esp8266/Arduino,hallard/Arduino,hallard/Arduino,esp8266/Arduino,Adam5Wu/Arduino,lrmoreno007/Arduino,Adam5Wu/Arduino,sticilface/Arduino,lrmoreno007/Arduino