Port #[rustc_layout_scalar_valid_range_start/end] to the new attribute parsing infrastructure

Signed-off-by: Jonathan Brouwer <jonathantbrouwer@gmail.com>

compiler/rustc_attr_parsing/src/context.rs

@@ -25,6 +25,9 @@ use crate::attributes::lint_helpers::{AsPtrParser, PubTransparentParser};
 use crate::attributes::loop_match::{ConstContinueParser, LoopMatchParser};
 use crate::attributes::must_use::MustUseParser;
 use crate::attributes::repr::{AlignParser, ReprParser};
+use crate::attributes::rustc_internal::{
+    RustcLayoutScalarValidRangeEnd, RustcLayoutScalarValidRangeStart,
+};
 use crate::attributes::semantics::MayDangleParser;
 use crate::attributes::stability::{
     BodyStabilityParser, ConstStabilityIndirectParser, ConstStabilityParser, StabilityParser,
@@ -126,6 +129,8 @@ attribute_parsers!(
         Single<OptimizeParser>,
         Single<PubTransparentParser>,
         Single<RustcForceInlineParser>,
+        Single<RustcLayoutScalarValidRangeEnd>,
+        Single<RustcLayoutScalarValidRangeStart>,
         Single<SkipDuringMethodDispatchParser>,
         Single<TrackCallerParser>,
         Single<TransparencyParser>,
@@ -269,6 +274,16 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
         })
     }
 
+    pub(crate) fn expected_integer_literal(&self, span: Span) -> ErrorGuaranteed {
+        self.emit_err(AttributeParseError {
+            span,
+            attr_span: self.attr_span,
+            template: self.template.clone(),
+            attribute: self.attr_path.clone(),
+            reason: AttributeParseErrorReason::ExpectedIntegerLiteral,
+        })
+    }
+
     pub(crate) fn expected_list(&self, span: Span) -> ErrorGuaranteed {
         self.emit_err(AttributeParseError {
             span,