fix: Correct calculation of debug symbol name length

[hun1er]

Summary

Addresses a critical compiler bug causing non-deterministic builds, resulting in .amxx files of varying sizes from identical source code.

Details

The issue was caused by an incorrect calculation of the debug symbol table size, which resulted in incorrect data being written to the executable. This resulted in non-deterministic builds and created a risk of server instability, as AMXX Mod X could crash when parsing corrupted debug information.
This patch corrects the calculation logic, ensuring the correct size of the debug symbol table.

Key Improvements

• Deterministic builds: The compiler now generates identical (byte-for-byte) binaries from the same source code.
• Valid .amxx binaries: Eliminates garbage data in the debug section.
• Enhanced stability: Prevents potential server crashes caused by parsing corrupted debug symbols.