Boot stub for HyperRAM reformatted

This does not have any functional changes, just removes some tabs and
defines HYPERRAM_BASE for readability

sw/cheri/sim_boot_stub/boot.S

@@ -1,16 +1,20 @@
 # Copyright lowRISC contributors.
 # Licensed under the Apache License, Version 2.0, see LICENSE for details.
 # SPDX-License-Identifier: Apache-2.0
-	.section .text.start, "ax", @progbits
-.zero 0x80
+  .section .text.start, "ax", @progbits
+  .zero 0x80
+
+  .globl start
+  .p2align 2
+  .type start,@function
+
+#define HYPERRAM_BASE 0x40000000
 
-	.globl start
-	.p2align 2
-    .type start,@function
 start:
   // Enable the ICache
   csrsi            0x7c0, 1
   auipcc           ct1, 0
-  li               t0, 0x40000000
+  // Jump to HyperRAM to start executing
+  li               t0, HYPERRAM_BASE
   csetaddr         ct1, ct1, t0
   cjr              ct1