mention boot linker script as suggeset by @Aaron1011

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>

Booting/linux-bootstrap-1.md

@@ -188,7 +188,7 @@ Continuing from before, now that the BIOS has chosen a boot device and transferr
 
 `grub_main` initializes the console, gets the base address for modules, sets the root device, loads/parses the grub configuration file, loads modules, etc. At the end of execution, `grub_main` moves grub to normal mode. `grub_normal_execute` (from `grub-core/normal/main.c`) completes the final preparations and shows a menu to select an operating system. When we select one of the grub menu entries, `grub_menu_execute_entry` runs, executing the grub `boot` command and booting the selected operating system.
 
-As we can read in the kernel boot protocol, the bootloader must read and fill some fields of the kernel setup header, which starts at the `0x01f1` offset from the kernel setup code. The kernel header [arch/x86/boot/header.S](https://github.com/torvalds/linux/blob/master/arch/x86/boot/header.S) starts from:
+As we can read in the kernel boot protocol, the bootloader must read and fill some fields of the kernel setup header, which starts at the `0x01f1` offset from the kernel setup code. You may look at the boot [linker script](https://github.com/torvalds/linux/blob/master/arch/x86/boot/setup.ld#L16) to make sure in this offset. The kernel header [arch/x86/boot/header.S](https://github.com/torvalds/linux/blob/master/arch/x86/boot/header.S) starts from:
 
 ```assembly
     .globl hdr