SAMA5 HSMCI: Correct multi-block DMA setup; Fixes related to DMA timeout.  Still problems with HSMCI DMA via XDMAC

SAMA4D5 HSMCI: Set burst size to 1, sample DMA registers on timeout, and don't return from transfer until BOTH the HSMCI transfer and DMA complete

SAMA5 LCDC: Back out the delay kludge.  Increase the LCDC input clock from MCK to 2*MCK was sufficient for all timing instbility problems

SAMA5 PIO: Fix a typo in Schmitt trigger configuration; Configure pin as a a vanilla input first so that final pin configuration is more read-able (i.e., easier to debug)

SAMA5 TWI: Some restructured needed by up_i2creset.  Also timeout needs to vary with the size of the transfer and if debug is on or not

Use sam_pio_forceclk() so that we can read the current state of an open-drain output in the TWI reset logic.

Add a new interface sam_pio_forceclk() that can be used to force PIO clocking on.  I am afraid I was too conservative with PIO clocking in the initial design; this is the price

SAMA5D3/4 HEAP: Add a configuration option to reserve DRAM for a framebuffer when executing out of DRAM.

NET: emoved all includes of uip.h; added includes of ip.h wherever needed.  Tried to fix problems of the now missing sneak inclusions because uip.h was removed.  There are probably a few of these that were missed.

AMA5 OHCI: Pointers to allocated port values were not being nullified after being deallocated.  This caused some assertions when debug was enabled