ARCH loading device tree overlays

Hi I am using the latest ARCH version:
Linux sd_card 4.16.3-1-ARCH #1 PREEMPT Sun Apr 22 01:10:55 UTC 2018 armv7l GNU/Linux

I am having difficulty getting capes working. I can see the .dtbo in /lib/firmware/. Specifically I am looking to get DLPDLCR2000-00A0.dtbo working.

I was able to get this cape working in debian by adding:
cape_disable=bone_capemgr.disable_partno=BB-BONELT-HDMI
cape_enable=bone_capemgr.enable_partno=DLPDLCR2000
To the uboot script for Kernel command line options. I have added these to boot.txt and recompiled to boot.src, but I am not seeing anything in dmesg where it is trying to load.

I have also checked /sys/devices and don’t see /bone_capemgr:

[root@sd_card devices]# ls
armv7_cortex_a8 breakpoint platform soc0 software system tracepoint virtual

Anyone have any insight on what I would need to do to get this working?