SAMA5 UDPHS: Fix error where bit was not cleared to acknowledge receipt of data and to setup for the next incoming data

SAMA5:  Don't use MMU PMD bufferable bit to try to control write-through vs write-back.  It does not work that way

Fix a build error when only USB device tracing is enabled (from David Sidrane).  Also an update to the USB tracing document

SAMA5: On some hardware, reconfiguring the PLL while executing out of NOR FLASH causes crashes.  This was fixed by David Sidrane by implementing RAM functions. The killer code is copied and executed from ISRAM and the crash is avoided.

SAMA5:  When booting from SDRAM, don't copy vectors to ISRAM.  Instread just set the VBAR register to add address of the vectors in SDRAM

SAMA5: Make sure the MMU and caches are disabled on power up; flush the vector region D-Cache after copying interrupt vectors; make sure that D-Cache, I-Cache, and TLBs are invalidated after modifying the AXI MATRIX remapping

sscanf(): Was returning the wrong number of conversions in many cases; Also, needs to return EOF if there were no conversions

SAMA5D3x-EK: Change name of all board-specific configuration variables so that there are no collisions with names of similar variables for other boards

SAM3/4: SPI and HSCMI drivers with now use the CMCC is available; The SPI driver will now handle word sizes greater than 8-bits

Add missing HSCMI configuration options; Make HSMCI configuration naming more compatible; Fix HSCMI clocking to use the CLKODD bit

net/netdev_findbyaddr.c:  Skip network devices that are in the down state.  They have no meaning address