Documentation: move DMA-mapping.txt to Doc/PCI/

Move DMA-mapping.txt to Documentation/PCI/.

DMA-mapping.txt was supposed to be moved from Documentation/ to
Documentation/PCI/.  The 00-INDEX files in those two directories
were updated, along with a few other text files, but the file
itself somehow escaped being moved, so move it and update more
text files and source files with its new location.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
cc:	Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 5244169..2a3fcc55 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -5,7 +5,7 @@
 
 This document describes the DMA API.  For a more gentle introduction
 phrased in terms of the pci_ equivalents (and actual examples) see
-DMA-mapping.txt
+Documentation/PCI/PCI-DMA-mapping.txt.
 
 This API is split into two pieces.  Part I describes the API and the
 corresponding pci_ API.  Part II describes the extensions to the API