[emsymbolizer] Move emsymbolizer.py to tools/ (NFC) (#25187)

This way the functions can be possibly reused from files from `tools/`.
Because we add it to
https://github.com/emscripten-core/emscripten/blob/main/tools/maint/create_entry_points.py,
users can access it from anywhere.

Author: aheejin

emsymbolizer.py renamed to tools/emsymbolizer.py

@@ -16,11 +16,16 @@
 import argparse
 from dataclasses import dataclass
 import json
+import os
 import re
 import subprocess
 import sys
 from typing import Optional
 
+__scriptdir__ = os.path.dirname(os.path.abspath(__file__))
+__rootdir__ = os.path.dirname(__scriptdir__)
+sys.path.insert(0, __rootdir__)
+
 from tools import shared
 from tools import webassembly
 

tools/maint/create_entry_points.py

@@ -55,6 +55,7 @@
   'emprofile': 'tools/emprofile',
   'emdwp': 'tools/emdwp',
   'emnm': 'tools/emnm',
+  'emsymbolizer': 'tools/emsymbolizer',
 }