linux-phytec-ti

Documentation: dt: Add PRUSS bindings

This patch adds the bindings for the Programmable Real-Time Unit
and Industrial Communication Subsystem (PRU-ICSS) present on various
TI SoCs (limited to OMAP architecture based SoCs for now). Details
have been added to include bindings for various core sub-modules
like the PRU Cores, the PRUSS Interrupt Controller, and other
sub-modules used for Industrial Communication purposes, covering
the MDIO, MII_RT and the IEP sub-modules. The binding uses all
standard DT properties without introducing any specific properties.

The binding status is also marked as unstable as the binding does
not cover all the sub-modules that are present within the PRU-ICSS,
and is also subject to improvements and changes upstream.

Signed-off-by: Suman Anna <s-anna@ti.com>