stm32h7 RTC and friends support
* stm32h7:Removed f7 in file path
* stm32f7:Fix overwritten IRQ enabled
System boot order calls clock_initialize then up_initalize.
clock_initialize was setting up the alarm IRQ
up_initalize is initializing the NVIC.
This most likely worked in the past due to a bug in the
NVIC init code that failed to clear the Interrupt enables.
That was fixed in 510b0f7e arch/arm/src: Correct all ARMv7-M
architectures. Interrupts were not be disabled correctly
on power up.
* stm32h7:Ported over F7 RTC
* nucleo-h743zi:Add RTC
Approved-by: Gregory Nutt <gnutt@nuttx.org>