[hmc58xx] add a delay before configuring the HMC58XX mag
[adc][stm32] fix accumulation freq when using ADC_WATCHDOG
[stm32] spektrum: remove unneeded gpio_enable_clock

that is already done in gpio_setup_output
add GEO_MAG message to send magnetic field
[stm32] fix sys_time_usleep

only use systick counter