Panic with proper error message if memory map is full

Author: phil-opp

src/bootinfo/memory_map.rs

@@ -22,6 +22,8 @@ impl MemoryMap {
     }
 
     pub fn add_region(&mut self, region: MemoryRegion) {
+        assert!(self.next_entry_index() < MAX_MEMORY_MAP_SIZE,
+            "too many memory regions in memory map");
         self.entries[self.next_entry_index()] = region;
         self.next_entry_index += 1;
         self.sort();