lmb: Set correct lmb flags for EFI memory map entries

When adding reserved memory areas from the EFI memory map set the NOMAP
flag when applicable. When this isn't done adding "no-map" flagged entries
from the fdt after receiving the same from the EFI memory map fails due
to non-matching flags.

Signed-off-by: Sjoerd Simons <sjoerd@collabora.com>