The renames are:
HAL_Delay -> mp_hal_delay_ms
sys_tick_udelay -> mp_hal_delay_us
sys_tick_get_microseconds -> mp_hal_ticks_us

And mp_hal_ticks_ms is added to provide the full set of timing functions.

Also, a separate HAL_Delay function is added which differs slightly from
mp_hal_delay_ms and is intended for use only by the ST HAL functions.