This PR provides implementation of ticker_free() function for the following boards:
ARCH_PRO
EV_COG_AD3029LZ
EV_COG_AD4050LZ
K22F
K64F
K82F
KW24D
KW41Z
LPC546XX
NRF51_DK
NRF52_DK
NUCLEO_F207ZG
NUCLEO_F401RE
NUCLEO_F429ZI
NUCLEO_F746ZG
REALTEK_RTL8195AM
- Move back the 16/32bit timer initialization in HAL_InitTick() and not in us_ticker_init()
- Use ticker_read_us() and us_ticker_read() in HAL_GetTick() to fix potential overflow issue with the 16bit timer
==> These corrections allow timer, rtc, sleep, tick tests to PASS