Enable CONFIG_OF_UPSTREAM to receive automatic
device tree updates for the Verdin AM62P.
Remove the now-obsolete device tree files:
- k3-am62p-verdin.dtsi
- k3-am62p-verdin-dev.dtsi
- k3-am62p-verdin-wifi.dtsi
- k3-am62p5-verdin-wifi-dev.dts
Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>