net: documentation: build a directory structure for drivers

Documentation/networking/ is full of cryptically named files with
driver documentation.  This makes finding interesting information
at a glance really hard.  Move all those files into a directory
called device_drivers (since not all drivers are for device) and
fix up references.

RFC v0.1 -> RFC v1:
 - also add .txt suffix to the files which are missing it (Quentin)

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Henrik Austad <henrik@austad.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
index 01fdc33..bb7e896 100644
--- a/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
+++ b/Documentation/devicetree/bindings/misc/fsl,qoriq-mc.txt
@@ -10,7 +10,7 @@
 etc.
 
 For an overview of the DPAA2 architecture and fsl-mc bus see:
-Documentation/networking/dpaa2/overview.rst
+Documentation/networking/device_drivers/freescale/dpaa2/overview.rst
 
 As described in the above overview, all DPAA2 objects in a DPRC share the
 same hardware "isolation context" and a 10-bit value called an ICID