update min_const_generics tests using default values for const params

The `const_generics_defaults` now handles them, and they correctly parse, so we can update these tests expecting a parser error .

Author: lqd

src/test/ui/const-generics/min_const_generics/default_function_param.rs

@@ -1,4 +1,4 @@
 fn foo<const SIZE: usize = 5>() {}
-                      //~^ ERROR expected one of `!`, `(`, `+`, `,`, `::`, `<`, or `>`, found `=`
+//~^ ERROR default values for const generic parameters are unstable
 
 fn main() {}

src/test/ui/const-generics/min_const_generics/default_function_param.stderr

@@ -1,8 +1,10 @@
-error: expected one of `!`, `(`, `+`, `,`, `::`, `<`, or `>`, found `=`
-  --> $DIR/default_function_param.rs:1:26
+error: default values for const generic parameters are unstable
+  --> $DIR/default_function_param.rs:1:28
    |
 LL | fn foo<const SIZE: usize = 5>() {}
-   |                          ^ expected one of 7 possible tokens
+   |                            ^
+   |
+   = help: add `#![feature(const_generics_defaults)]` to the crate attributes to enable
 
 error: aborting due to previous error
 

src/test/ui/const-generics/min_const_generics/default_trait_param.rs

@@ -1,4 +1,4 @@
 trait Foo<const KIND: bool = true> {}
-                        //~^ ERROR expected one of `!`, `(`, `+`, `,`, `::`, `<`, or `>`, found `=`
+//~^ ERROR default values for const generic parameters are unstable
 
 fn main() {}

src/test/ui/const-generics/min_const_generics/default_trait_param.stderr

@@ -1,8 +1,10 @@
-error: expected one of `!`, `(`, `+`, `,`, `::`, `<`, or `>`, found `=`
-  --> $DIR/default_trait_param.rs:1:28
+error: default values for const generic parameters are unstable
+  --> $DIR/default_trait_param.rs:1:30
    |
 LL | trait Foo<const KIND: bool = true> {}
-   |                            ^ expected one of 7 possible tokens
+   |                              ^^^^
+   |
+   = help: add `#![feature(const_generics_defaults)]` to the crate attributes to enable
 
 error: aborting due to previous error