arch: arm: fix mpu compiler warnings

What is the change?
 - Use a macro that search for "zephyr, memory-attr" in only
   those nodes that have the property "zephyr, memory-regions".
 - Fixes #83448.

Why is this needed?
 - Using `DT_REG_ADDR` inside `DT_FOREACH_STATUS_OKAY_NODE_VARGS` can
   lead to compiler warnings if a devicetree node has an addresses
   larger than 64bits. An example of such node is wm8904 i3c with 92
   bit encoding addresses `audio_codec: wm8904@1a0000000000000000`.
   We can avoid this warning since this is not applicable for nodes
   that have the attribute "zephyr,memory-regions".

Signed-off-by: Sudan Landge <sudan.landge@arm.com>