Rollup merge of #85920 - luqmana:wasm-linker-tweaks, r=petrochenkov

Tweak wasm_base target spec to indicate linker is not GNU and update linker inferring logic for wasm-ld.

Reported via [Zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/wasi.20linker.20unknown.20argument.3A.20--as-needed): we try passing `--as-needed` to the linker if it's GNU ld which `wasm-ld` is not. Usually this isn't an issue for wasm as we would use the WasmLd linker driver but because the linker in question (`wasm32-unknown-wasi-wasm-ld`) ended with `-ld` our linker inferring [logic](f64503eb55/compiler/rustc_codegen_ssa/src/back/link.rs (L957-L1040)) used the `GccLinker` implementations. (UPD: The linker inferring logic actually didn't apply in this case because the linker is actually invoked through gcc in the reported issue. But it's still worth updating the logic I think.)

This change then has 2 parts:
1. Update wasm_base target spec to indicate `linker_is_gnu: false` plus a few additions of `target.is_like_wasm` to handle flags `wasm-ld` does in fact support.
2. Improve the linker detection logic to properly determine the correct flavor of wasm linker we're using when we can.

We need to add the new `target.is_like_wasm` branches to handle the case where the "linker" used could be something like clang which would then under the hood call wasm-ld.

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1199,6 +1199,8 @@ fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
                     || stem.ends_with("-clang")
                 {
                     LinkerFlavor::Gcc
+                } else if stem == "wasm-ld" || stem.ends_with("-wasm-ld") {
+                    LinkerFlavor::Lld(LldFlavor::Wasm)
                 } else if stem == "ld" || stem == "ld.lld" || stem.ends_with("-ld") {
                     LinkerFlavor::Ld
                 } else if stem == "link" || stem == "lld-link" {