* Add GPIO interrupt support for Nordic GPIO.
* arch/ARM/Nordic/drivers/nrf_common/nrf-gpio-tasks_and_events.ad[sb]:
Added subprograms to enable, test for presence, acknowledge and
disable both channel and port interrupts.
* Correct style warnings for Nordic GPIO interrupts.
* Match Nordic GPIO changes to AdaCore style.
* arch/ARM/Nordic/drivers/nrf_common/nrf-gpio-tasks_and_events.ads
(Channel_Event_Is_Set): renamed to Channel_Event_Set.
(Port_Event_Is_Set): similarly.
* arch/ARM/Nordic/drivers/nrf_common/nrf-gpio-tasks_and_events.adb:
likewise. Keyword 'is' always on new line.
* Add RISC-V performance CSR support
* RISC-V Read_CSR_64: fix rv32 version
* RISC-V improve CSR support
Add sub-program to swap, set bits, clear bits, etc.
Instantiate sub-programs for all machine CSRs.
* Olimex STM32-H405 board support
* Add STM32-H405 to build_all_examples.py, fix for style checks
* Use stm32f4 runtime for STM32-H405 board
* Add STM32_H405 to board_projects_generator.py
* arch/ARM/cortex_m/src/semihosting.adb (Write_0): Data is of new
type Byte_Array, which is a new UInt8_Array with volatile
components (FSF GCC was miscompiling at -O3).
* Added PMW3901 (flow) sensor support.
Includes general-purpose check for whether this SPI port is clocked.
* components/src/motion/pmw3901/pmw3901.ads: new.
* components/src/motion/pmw3901/pmw3901.adb: new.
* components/src/motion/pmw3901/pmw3901-is_clocked.adb: new. The
check for the associated SPI port being clocked is implemented
as a separate because it really belongs in the Device package.
* PMW3901 driver no longer depends on STM32.
* components/src/motion/pmw3901/pmw3901.ads: remove dependency on
STM32, replace by HAL equivalent.
(Initialize): replace precondition using Is_Clocked to 'not
Is_Initialized'.
(Is_Clocked): removed.
* components/src/motion/pmw3901/pmw3901.adb: likewise.
* components/src/motion/pmw3901/pmw3901-is_clocked.adb: removed.
* PMW3901 copyright/clarity updates.
* components/src/motion/pmw3901/pmw3901.adb: Updated copyright
notice, as requested.
* components/src/motion/pmw3901/pmw3901.ads: Likewise.
(Motion's rep spec): moved to private part, to reduce clutter.
