lib: lmb: extend lmb for checks at load time

This adds two new functions, lmb_alloc_addr and
lmb_get_unreserved_size.

lmb_alloc_addr behaves like lmb_alloc, but it tries to allocate a
pre-specified address range. Unlike lmb_reserve, this address range
must be inside one of the memory ranges that has been set up with
lmb_add.

lmb_get_unreserved_size returns the number of bytes that can be
used up to the next reserved region or the end of valid ram. This
can be 0 if the address passed is reserved.

Added test for these new functions.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/include/lmb.h b/include/lmb.h
index f04d058..7d7e2a7 100644
--- a/include/lmb.h
+++ b/include/lmb.h
@@ -38,6 +38,9 @@
 			    phys_addr_t max_addr);
 extern phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align,
 			      phys_addr_t max_addr);
+extern phys_addr_t lmb_alloc_addr(struct lmb *lmb, phys_addr_t base,
+				  phys_size_t size);
+extern phys_size_t lmb_get_unreserved_size(struct lmb *lmb, phys_addr_t addr);
 extern int lmb_is_reserved(struct lmb *lmb, phys_addr_t addr);
 extern long lmb_free(struct lmb *lmb, phys_addr_t base, phys_size_t size);