ARM: dts: OMAP4: Add standby info for IPU and DSP

Add the data for the "ti,rproc-standby-info" property for
the DSP and IPU remoteproc processor nodes. This data is
common to all OMAP4 boards, and is required by the OMAP
remoteproc driver to implement suspend/resume for the OMAP4
remoteproc devices.

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