adapt eq3_timer for esp32c3 build

[Digit-al]

Hello,
I am trying to build the project for an esp32c3 but it's failing on the eq3_timer as the struct differs with the esp32 (cnt_low, cnt_high and update don't exist in the timer_group_struct.h for esp32c3)
I am should admit I am a complete newbie with esp32 so could you help me to adapt the code ?
Thanks a lot in advance