Unconditionally set no-f16-f128 for compiler_builtins

With the v2 resolver, this has the intended behavior of building
compiler_builtins. Unfortunately, this exposes the fact that the current
stage0 compiler cannot build the `f16` and `f128` implementation of
compiler_builtins.

Unconditionally disable `f16` and `f128` for now so we can update the
resolver.

library/alloc/Cargo.toml

@@ -10,10 +10,7 @@ edition = "2021"
 
 [dependencies]
 core = { path = "../core" }
-compiler_builtins = { version = "0.1.114", features = ['rustc-dep-of-std'] }
-
-[target.'cfg(not(any(target_arch = "aarch64", target_arch = "x86", target_arch = "x86_64")))'.dependencies]
-compiler_builtins = { version = "0.1.114", features = ["no-f16-f128"] }
+compiler_builtins = { version = "0.1.114", features = ["rustc-dep-of-std", "no-f16-f128"] }
 
 [dev-dependencies]
 rand = { version = "0.8.5", default-features = false, features = ["alloc"] }