uefiboot: build UEFIPAYLOAD.fd in Docker.
uefiboot: build UEFIPAYLOAD.fd in Docker.

Signed-off-by: Cheng-Chieh Huang <f7cd064739ef46f59034465200cb60c0fcfaca4e@google.com>

u-root/u-root,u-root/u-root,u-root/u-root