linker: devicetree_regions: escape special characters
linker: devicetree_regions: escape special characters

Escape characters <> (generate warnings for the HTML build).

Signed-off-by: Gerard Marull-Paretas <bedb45f43a286e49f4dcda039a436b216ae61ef3@nordicsemi.no>

zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr