Merge branch 'testing' of https://github.com/fedetft/miosix-kernel into gcc-9.2.0

miosix/_examples/atsam4l_lcd/main.cpp

miosix/_examples/datalogger/Logger.cpp

miosix/_examples/datalogger/Logger.h

miosix/_examples/datalogger/main.cpp

miosix/_examples/streamwriter/streamwriter.cpp

miosix/_tools/delay_test/delay_test.cpp

miosix/_tools/fs_backend/backend_benchmark.cpp

..._lpc2000/lpc2138_miosix_board/interfaces-impl/gpio_impl.h

...ix/arch/cortexM0_stm32/common/interfaces-impl/gpio_impl.h

.../arch/cortexM3_efm32gg/common/interfaces-impl/gpio_impl.h

...32gg/efm32gg332f1024_wandstem/interfaces-impl/gpioirq.cpp

...ix/arch/cortexM3_stm32/common/interfaces-impl/gpio_impl.h

.../arch/cortexM3_stm32f2/common/interfaces-impl/gpio_impl.h

.../arch/cortexM3_stm32l1/common/interfaces-impl/gpio_impl.h

...texM4_atsam4l/atsam4lc2aa_generic/interfaces-impl/bsp.cpp

miosix/arch/cortexM4_atsam4l/common/drivers/clock.cpp

miosix/arch/cortexM4_atsam4l/common/drivers/clock.h

miosix/arch/cortexM4_atsam4l/common/drivers/lcd.cpp

miosix/arch/cortexM4_atsam4l/common/drivers/lcd.h

.../arch/cortexM4_atsam4l/common/interfaces-impl/gpio_impl.h