layout: Make romentry.name a pointer

This should provide more flexibility while we don't have to allocate
256B extra per layout entry.

Change-Id: Ibb903113550ec13f43cbbd0a412c8f35fe1cf454
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/33515
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

layout.h

@@ -39,7 +39,7 @@ struct romentry {
 	chipoff_t start;
 	chipoff_t end;
 	bool included;
-	char name[256];
+	char *name;
 };
 
 struct flashrom_layout {