dtb files are not installed to /usr/share by linux-postmarketos

When building/installing linux-postmarketos for the RX51, the dtb files are not installed to /usr/share/dtb. I see this in the pmbootstrap log file:

cat: can't open '/usr/share/dtb/omap3-n900.dtb': No such file or directory  

I did some digging around, looks like the the linux-postmarketos APKBUILD is actually installing dtb files to /usr/share/dts... but for some reason not even this happens with the rx51 and the latest from master. The condition in the APKBUILD seems to be true when I look in the build directory, the arch/arm/boot/dts path exists there, so I have no idea why this is not being picked up by the package() method in the APKBUILD.

I have no /usr/share/dtb or /usr/share/dts directory in the device rootfs chroot (hence the error in the log from mkinit.sh)

The end result of this issue is that master does not boot on the RX51, since the kernel is unable to find the sdcard.