EFM32 USART setup: Computation of BAUD includes shift; Eliminate additional shift.  From  Pierre-noel Bouteville

Netwoek:  Ada a parameter to netdev_register() to indicate the link protocol supported by the driver.  Use this value to replace some logic commited yesterday

Remove the definition of INT_FAST32_MIN which is already defined in stdint.h (the correct location).  From Lorenz Meier.