pios_semaphore: added
all target makefiles: added pios_semaphore.c
pios_flash_jedec: use pios_semaphore
all pios_flash_internal: use pios_semaphore
all pios_spi: use pios_sempaphore
all pios_i2c: use pios_semaphore
pios_hmc5883: use pios_semaphore
pios i2c and spi: fixed copyright header
pios_semaphore: add compile time check for dependencies
pios_semaphore requires either PIOS_INCLUDE_FREERTOS or PIOS_INCLUDE_IRQ to be defined