Relocatable DOL hack

[riptl]

Update gen_asm to create relocatable assembly for DOL .text section.

Steal approach used by @camthesaxman's doldisasm

1. lis/la effective address matcher
2. mechanism to export the refs from gen_asm on .text to gen_asm in .data (probably easiest here is to just modify symbols.txt on the fly)
3. ~~regex to replace offsets~~ use capstone label callback to replace literal offsets with symbol refs

[riptl]

Picking this up today.