Remove redundant 'spirv-val failed' note from validation errors

The error context already makes it clear this is a validation error.

Author: LegNeato

crates/rustc_codegen_spirv/src/validation_err.rs

@@ -72,7 +72,6 @@ impl<'a> ValidationErrorContext<'a> {
     /// Emits a generic validation error without rich formatting.
     fn emit_generic_error(&self, error: &spirv_tools::val::ValidatorError) {
         let mut err = self.sess.dcx().struct_err(error.to_string());
-        err.note("spirv-val failed");
         err.note(format!("module `{}`", self.filename.display()));
         err.emit();
     }
@@ -128,7 +127,6 @@ impl<'a> ValidationErrorContext<'a> {
                 }
             }
 
-            err.note("spirv-val failed");
             err.note(format!("module `{}`", self.filename.display()));
             err.emit();
         } else {
@@ -137,7 +135,6 @@ impl<'a> ValidationErrorContext<'a> {
                 "{:?} variable `{}` at location {} conflicts with `{}`",
                 storage_class, second_name_display, location, first_name_display
             ));
-            err.note("spirv-val failed");
             err.note(format!("module `{}`", self.filename.display()));
             err.note(format!(
                 "variables `{}` and `{}` both use location {} component {}",
@@ -189,7 +186,6 @@ impl<'a> ValidationErrorContext<'a> {
             err.note(format!("generated SPIR-V:\n{}", context));
         }
 
-        err.note("spirv-val failed");
         err.note(format!("module `{}`", self.filename.display()));
         err.emit();
     }

tests/compiletests/ui/lang/core/ref/member_ref_arg-broken.stderr

@@ -41,7 +41,6 @@ error: OpLoad cannot use pointer `%38` because it was produced by OpCompositeExt
    = note: generated SPIR-V:
                   %38 = OpCompositeExtract ...
                -> %39 = OpLoad %38 ...
-   = note: spirv-val failed
    = note: module `$TEST_BUILD_DIR/lang/core/ref/member_ref_arg-broken`
 
 error: aborting due to 1 previous error; 4 warnings emitted

tests/compiletests/ui/spirv-attr/location_assignment/explicit_overlap.stderr

@@ -53,7 +53,6 @@ note: variable `out1` already uses location 1 component 0
 LL | pub fn main(#[spirv(location = 0)] out1: &mut Mat4, #[spirv(location = 1)] out2: &mut Vec2) {
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = help: `out1` is at location 0 but type `spirv_std::glam::Mat4` consumes 4 locations (0–3)
-   = note: spirv-val failed
    = note: module `<normalized>`
 
 error: aborting due to 1 previous error