add teeos std impl

Signed-off-by: 袁浩 <yuanhao34@huawei.com>

compiler/rustc_target/src/spec/targets/aarch64_unknown_teeos.rs

@@ -4,7 +4,6 @@ pub fn target() -> Target {
     let mut base = base::teeos::opts();
     base.features = "+strict-align,+neon,+fp-armv8".into();
     base.max_atomic_width = Some(128);
-    base.linker = Some("aarch64-linux-gnu-ld".into());
 
     Target {
         llvm_target: "aarch64-unknown-none".into(),