Enable LSX feature for LoongArch Linux targets

Author: heiher

compiler/rustc_target/src/spec/targets/loongarch64_unknown_linux_gnu.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
 options:TargetOptions{
 code_model:Some(CodeModel::Medium),
 cpu:"generic".into(),
-features:"+f,+d".into(),
+features:"+f,+d,+lsx".into(),
 llvm_abiname:"lp64d".into(),
 max_atomic_width:Some(64),
 supported_sanitizers:SanitizerSet::ADDRESS

compiler/rustc_target/src/spec/targets/loongarch64_unknown_linux_musl.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
 options:TargetOptions{
 code_model:Some(CodeModel::Medium),
 cpu:"generic".into(),
-features:"+f,+d".into(),
+features:"+f,+d,+lsx".into(),
 llvm_abiname:"lp64d".into(),
 max_atomic_width:Some(64),
 crt_static_default:false,