Booting: Add coreboot source code links to linux-bootstrap-1.md

The coreboot source code has changed since this section was written.
reset16.inc and reset16.ld do not exist in the master branch
of coreboot. Add links to the source code of coreboot v4.11 to point
to the correct files.

Booting/linux-bootstrap-1.md

@@ -73,7 +73,7 @@ The starting address is formed by adding the base address to the value in the EI
 '0xfffffff0'
 ```
 
-We get `0xfffffff0`, which is 16 bytes below 4GB. This point is called the [reset vector](https://en.wikipedia.org/wiki/Reset_vector). It's the memory location at which the CPU expects to find the first instruction to execute after reset. It contains a [jump](https://en.wikipedia.org/wiki/JMP_%28x86_instruction%29) (`jmp`) instruction that usually points to the [BIOS](https://en.wikipedia.org/wiki/BIOS) (Basic Input/Output System) entry point. For example, if we look in the [coreboot](https://www.coreboot.org/) source code (`src/cpu/x86/16bit/reset16.inc`), we see:
+We get `0xfffffff0`, which is 16 bytes below 4GB. This point is called the [reset vector](https://en.wikipedia.org/wiki/Reset_vector). It's the memory location at which the CPU expects to find the first instruction to execute after reset. It contains a [jump](https://en.wikipedia.org/wiki/JMP_%28x86_instruction%29) (`jmp`) instruction that usually points to the [BIOS](https://en.wikipedia.org/wiki/BIOS) (Basic Input/Output System) entry point. For example, if we look in the [coreboot](https://www.coreboot.org/) source code ([src/cpu/x86/16bit/reset16.inc](https://review.coreboot.org/plugins/gitiles/coreboot/+/refs/heads/4.11_branch/src/cpu/x86/16bit/reset16.inc)), we see:
 
 ```assembly
     .section ".reset", "ax", %progbits
@@ -87,7 +87,7 @@ _start:
 
 Here we can see the `jmp` instruction [opcode](http://ref.x86asm.net/coder32.html#xE9), which is `0xe9`, and its destination address at `_start16bit - ( . + 2)`.
 
-We also see that the `reset` section is `16` bytes and is compiled to start from the address `0xfffffff0` (`src/cpu/x86/16bit/reset16.ld`):
+We also see that the `reset` section is `16` bytes and is compiled to start from the address `0xfffffff0` ([src/cpu/x86/16bit/reset16.ld](https://review.coreboot.org/plugins/gitiles/coreboot/+/refs/heads/4.11_branch/src/cpu/x86/16bit/reset16.ld)):
 
 ```
 SECTIONS {