[lld] [lld][WebAssembly]: Restore non-pie dynamic-linking executable (PR #108146)

[Sam Clegg via llvm-commits]

================
@@ -913,7 +913,8 @@ static void createSyntheticSymbols() {
   }
 
   if (ctx.isPic ||
-      config->unresolvedSymbols == UnresolvedPolicy::ImportDynamic) {
+      config->unresolvedSymbols == UnresolvedPolicy::ImportDynamic ||
+      !config->isStatic) {
----------------
sbc100 wrote:

I wonder if can replace `ctx.isPic` with ` !config->isStatic` above?    Does it make sense to allow `-shared` + `-static`?  Or `-pie` + `-static`?

I wonder if we need a better way to detect if dynamic linking used at all since you can imagine a case where `isStatic` is true, but we do have dynamic linking.  For example:

```
$ wasm-ld foo.o -Bdynamic -ldylib -Bstatic -lstaticlib
```

In that case since `-Bstatic` comes last on the command line the `config->isStatic` will be false even though we include libdylib.so dyanmically.

Another example:

```
wasm-ld foo.o libdylib.so libstaticlib.a
```

Here `config->isStatic` will remain false even though dynamic linking is used.
```

https://github.com/llvm/llvm-project/pull/108146