arm64: dts: ti: hummingboard-t: add overlays for m.2 pci-e and usb-3

HummingBoard-T features two M.2 connectors labeled "M1" and "M2".
The single SerDes lane of the SoC can be routed to either M1 pci-e
signals, or M2 usb-3 signals by a gpio-controlled mux.

Add overlays for each configuration.

Signed-off-by: Josua Mayer <josua@solid-run.com>
Link: https://lore.kernel.org/r/20240219-add-am64-som-v7-4-0e6e95b0a05d@solid-run.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>