Add "flags" in lmb_property to save the "no-map" property of
reserved region and a new function lmb_reserve_flags() to check
this flag.
The default allocation use flags = LMB_NONE.
The adjacent reserved memory region are merged only when they have
the same flags value.
This patch is partially based on flags support done in Linux kernel
mm/memblock .c (previously lmb.c); it is why LMB_NOMAP = 0x4, it is
aligned with MEMBLOCK_NOMAP value.
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com> Reviewed-by: Simon Glass <sjg@chromium.org>