Forcing u-boot to detect USB3 storage

[t4_4t]

> sda7:               linux-root
> mmcblk1p7:    linux-root
That is because the labels are duplicated.

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If you change the label of sda7, it works properly.

Eg) sda7: linux-root-sd

And then change the following.
root=LABEL=linux-root  ->  root=LABEL=linux-root-sd

Another way is to change the root=/dev/sda7.
However, if you connect multiple "usb-device" in this method, the device file name may change.
Therefore, It is better to specify by LABEL or UUID or PARTUUID.

In this way,
you can reliably mount the specified device regardless of the increase or decrease in the number of "usb-device" connections.