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/layout.c b/layout.c
index a604a7b..47db484 100644
--- a/layout.c
+++ b/layout.c
@@ -25,7 +25,7 @@
 #include "layout.h"
 
 static struct romentry entries[MAX_ROMLAYOUT];
-static struct flashrom_layout global_layout = { entries, 0 };
+static struct flashrom_layout global_layout = { entries, MAX_ROMLAYOUT, 0 };
 
 struct flashrom_layout *get_global_layout(void)
 {
@@ -75,9 +75,9 @@
 	while (!feof(romlayout)) {
 		char *tstr1, *tstr2;
 
-		if (layout->num_entries >= MAX_ROMLAYOUT) {
-			msg_gerr("Maximum number of ROM images (%i) in layout "
-				 "file reached.\n", MAX_ROMLAYOUT);
+		if (layout->num_entries >= layout->capacity) {
+			msg_gerr("Maximum number of ROM images (%zu) in layout "
+				 "file reached.\n", layout->capacity);
 			goto _close_ret;
 		}
 		if (2 != fscanf(romlayout, "%255s %255s\n", tempstr, tempname))