Add 'rela' to spell check dictionary

RELA is a valid ELF term for relocation entries with explicit addends.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: rtfeldman

typos.toml

@@ -24,3 +24,4 @@ typ = "typ"
 ba = "ba"
 sigfault = "sigfault"
 nd = "nd"
+rela = "rela"