mtd: Move fdt partition documentation to a seperate file

Partitions are described in the same way for all mtd devices when using
devicetree, move the documentation to a separate file and add references
to it.

Signed-off-by: Jamie Lentin <jm@lentin.co.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
index 80152cb..a63c2bd7 100644
--- a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
+++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
@@ -23,27 +23,8 @@
  - vendor-id : Contains the flash chip's vendor id (1 byte).
  - device-id : Contains the flash chip's device id (1 byte).
 
-In addition to the information on the mtd bank itself, the
-device tree may optionally contain additional information
-describing partitions of the address space.  This can be
-used on platforms which have strong conventions about which
-portions of a flash are used for what purposes, but which don't
-use an on-flash partition table such as RedBoot.
-
-Each partition is represented as a sub-node of the mtd device.
-Each node's name represents the name of the corresponding
-partition of the mtd device.
-
-Flash partitions
- - reg : The partition's offset and size within the mtd bank.
- - label : (optional) The label / name for this partition.
-   If omitted, the label is taken from the node name (excluding
-   the unit address).
- - read-only : (optional) This parameter, if present, is a hint to
-   Linux that this partition should only be mounted
-   read-only.  This is usually used for flash partitions
-   containing early-boot firmware images or data which should not
-   be clobbered.
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
 
 Example: