fix: correctd HEAP_SIZE comment (8 MiB, not 100 KiB)

Author: abhiprd2000

src/allocator.rs

@@ -9,7 +9,7 @@ use x86_64::{
 };
 
 pub const HEAP_START: usize = 0x_4444_4444_0000;
-pub const HEAP_SIZE: usize = 8 * 1024 * 1024; // 100 KiB
+pub const HEAP_SIZE: usize = 8 * 1024 * 1024; // 8 MiB
 
 #[global_allocator]
 static ALLOCATOR: LockedHeap = LockedHeap::empty();