Avoid code duplication by using binding

Author: phil-opp

bios/stage-2/src/main.rs

@@ -103,7 +103,7 @@ fn start(disk_number: u16, partition_table_start: *const u8) -> ! {
     writeln!(screen::Writer, "Loading ramdisk...").unwrap();
     let ramdisk_len = match try_load_file(
         "ramdisk",
-        KERNEL_DST.wrapping_add(kernel_page_size * 4096),
+        ramdisk_start,
         &mut fs,
         &mut disk,
         disk_buffer,