I’m going to be trying to get SPI working myself shortly.
I noticed that you changed the wrong device tree file (at least if you’re trying to change it on the TX1). The TX1 only loads one of the .dtb files at the start, you can delete the others with no effect. From dmesg:
[ 0.000000] DTS File Name: arch/arm64/boot/dts/tegra210-jetson-tx1-p2597-2180-a01-devkit.dts
If you want the changes made in tegra210-jetson-cv-base-p2597-2180-a00.dtb to take effect you’ll need to recompile the dtbs (make dtbs) so that your changes are written in to arch/arm64/boot/dts/tegra210-jetson-tx1-p2597-2180-a01-devkit.dtb