Fix review comments on amdgpu target specification

Author: Flakebi

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

@@ -31,9 +31,15 @@ pub(crate) fn target() -> Target {
 
             // amdgpu backend does not support libcalls.
             no_builtins: true,
+            simd_types_indirect: false,
 
-            // Needed to use `cdylib` crate type.
+            // Allow `cdylib` crate type.
             dynamic_linking: true,
+            only_cdylib: true,
+            executables: false,
+
+            // The LLVM backend does not support stack canaries for this target
+            supports_stack_protector: false,
 
             ..Default::default()
         },