In this application SERCOM4 is connected to the EDBG USART lines through
which the SAML22 Xplained pro will communicate with the PC terminal
application. configure_console() function initializes the
SERCOM USART module connected to the EDBG USART, configures the
corresponding USART pins and the studio serial initializations for the
standard library APIs (like scanf, printf, etc,.)