[Buildroot] PocketBeagle: U-Boot 2021.04 is broken

[Enoch]

Hello buildroot-ers:

A working defconfig fails with the latest U-Boot version selected. Is it
working for anyone using TI's AM335X SOC?

Thanks, Enoch.

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U-Boot SPL 2021.04 (May 07 2021 - 18:30:29 -0400)
Trying to boot from MMC1


U-Boot 2021.04 (May 07 2021 - 18:30:29 -0400)

CPU  : AM335X-GP rev 2.1
Model: TI AM335x PocketBeagle
DRAM:  512 MiB
WDT:   Started with servicing (60s timeout)
Could not initialize timer (err -19)
Could not initialize timer (err -19)