Lots of simple code cleanup for EDMA:

 - KernelDoc updates (biggest part by volume):  fixes; keep only
   one copy of the function description, next to its definition;
   convert most function descriptions to kerneldoc.

 - Message fixup in EDMA support: use just newline, not CRNL;
   use %08x for 32 bit values.

 - Comment a couple fault handling glitches, and fix one.

 - Change parameters of the davinci_set_dma_{src,dest}_index() and
   davinci_set_dma_transfer_params() functions to use explicit
   widths (s16, u16) not implicit (short, unsigned short).

 - Switch davinci_set_dma_{src,dest}_params() to use dma_addr_t for
   DMA addresses.

No functional changes here, except insisting that davinci_stop_dma()
do nothing unless it's given a valid DMA channel.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>