Inline can_begin_literal_maybe_minus call into two places.

It's clearer this way, because the `Interpolated` cases in
`can_begin_const_arg` and `is_pat_range_end_start` are more permissive
than the `Interpolated` cases in `can_begin_literal_maybe_minus`.

compiler/rustc_ast/src/token.rs

@@ -558,9 +558,10 @@ impl Token {
     /// Returns `true` if the token can appear at the start of a const param.
     pub fn can_begin_const_arg(&self) -> bool {
         match self.kind {
-            OpenDelim(Delimiter::Brace) => true,
+            OpenDelim(Delimiter::Brace) | Literal(..) | BinOp(Minus) => true,
+            Ident(name, IdentIsRaw::No) if name.is_bool_lit() => true,
             Interpolated(ref nt) => matches!(&**nt, NtExpr(..) | NtBlock(..) | NtLiteral(..)),
-            _ => self.can_begin_literal_maybe_minus(),
+            _ => false,
         }
     }