beagley-ai-using-imx219-csi-cameras: use correct device-tree k3-am67a-beagley-ai.dtb

Signed-off-by: Robert Nelson <robertcnelson@gmail.com>

boards/beagley/ai/demos/beagley-ai-using-imx219-csi-cameras.rst

@@ -59,7 +59,7 @@ Your ``/boot/firmware/extlinux/extlinux.conf`` file should look something like t
       kernel /Image
       append console=ttyS2,115200n8 root=/dev/mmcblk0p2 ro rootfstype=ext4 rootwait net.ifnames=0
       fdtdir /
-      fdt /ti/k3-j722s-beagley-ai.dtb
+      fdt /ti/k3-am67a-beagley-ai.dtb
       fdtoverlays /overlays/k3-am67a-beagley-ai-csi0-imx219.dtbo
       initrd /initrd.img
 
@@ -131,4 +131,4 @@ Troubleshooting
       6:      microSD (csi0 ov5640)
       7:      microSD (default)
    Enter choice: 4
-      4:      microSD (csi0 imx219)
+      4:      microSD (csi0 imx219)
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