lmb: remove lmb_region.size

Remove the unused field size of struct lmb_region as it is initialized to 0
and never used after in lmb library.

See Linux kernel commit 4734b594c6ca ("memblock: Remove memblock_type.size
and add memblock.memory_size instead")

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>

include/lmb.h

@@ -21,7 +21,6 @@ struct lmb_property {
 
 struct lmb_region {
 	unsigned long cnt;
-	phys_size_t size;
 	struct lmb_property region[MAX_LMB_REGIONS+1];
 };