Add option to skip DHCP in pxeboot and just specify a remote file
Add option to skip DHCP in pxeboot and just specify a remote file

Signed-off-by: Colin Mitchell <edcb7a4d344eee58b9ea56a46bf6c3a62cd814de@google.com>

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