layout: Add `capacity` field

Use it to keep track of the size of the `entries` array. An interim
solution until we have dynamic allocation.

Change-Id: Ib5f431bc0a72a79a53fa1376c3417942b19dd3a0
Signed-off-by: Nico Huber <nico.h@gmx.de>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/33516
Original-Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Original-Reviewed-by: Anastasia Klimchuk <aklm@chromium.org>
Original-Reviewed-by: Peter Marheine <pmarheine@chromium.org>
Original-Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/72212
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/libflashrom.c b/libflashrom.c
index e390a02..b9c2d35 100644
--- a/libflashrom.c
+++ b/libflashrom.c
@@ -387,7 +387,7 @@
 	if (!fmap || !l)
 		return 1;
 
-	if (l->num_entries + fmap->nareas > MAX_ROMLAYOUT) {
+	if (l->num_entries + fmap->nareas > l->capacity) {
 		msg_gerr("Cannot add fmap entries to layout - Too many entries.\n");
 		return 1;
 	}