It looks like the u-root 'master' branch was renamed to 'main'.
Change-Id: I384ba66289a49bf226b505615bd16bdf85612c1a
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62590
Reviewed-by: Christian Walter <christian.walter@9elements.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>