Fix GetProcAddress issue on ARM64 (#5)

See [TeamTofuShop/segatools/issues/20](https://gitea.tendokyu.moe/TeamTofuShop/segatools/issues/20).

This PR adds `pe_is_arm64` for detecting ARM64 systems and `pe_get_arm64_real_proc` for retrieving the real thread address.

I'm still getting familiar with the project, so I’d really appreciate any feedback, suggestions, or corrections.

Reviewed-on: https://gitea.tendokyu.moe/TeamTofuShop/capnhook/pulls/5
Co-authored-by: oldkingOK <oldkingok@qq.com>
Co-committed-by: oldkingOK <oldkingok@qq.com>

hook/process.c

@@ -73,6 +73,9 @@ static HRESULT process_hijack_try_thread(
 
     exe_entry = pe_get_entry_point(exe);
     ntstart = GetProcAddress(ntdll, "RtlUserThreadStart");
+    if (pe_is_arm64()) {
+        ntstart = pe_thunk_resolve(ntstart);
+    }
 
     if (ntstart == NULL) {
         /* TODO Deal with WinXP, for the poor souls still stuck on that OS.