dt-bindings: soc: ti,omap-dmm: Convert to DT schema

dt-bindings: soc: ti,omap-dmm: Convert to DT schema

Convert the TI OMAP Dynamic Memory Manager (DMM) dt binding
from text format to DT schema.

During conversion following changes were made:
- Move file from /bindings/arm/omap to /bindings/soc/ti/
- Make the 'ti,hwmods' property optional and mark it deprecated as it is
  no longer used, it is kept to support legacy dtbs.
- Add the missing required property 'interrupts' to example node.

Signed-off-by: Bhargav Joshi <j.bhargav.u@gmail.com>
Link: https://patch.msgid.link/20260605-ti-omap-dmm-v2-1-1b460742ec83@gmail.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>