Rename core_pattern_type and core_pattern_types lib feature gates to pattern_type_macro

That's what the gates are actually gating, and the single char difference in naming was not helpful either

Author: oli-obk

core/src/lib.rs

@@ -345,7 +345,7 @@ pub mod net;
 pub mod option;
 pub mod panic;
 pub mod panicking;
-#[unstable(feature = "core_pattern_types", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 pub mod pat;
 pub mod pin;
 #[unstable(feature = "random", issue = "130703")]

core/src/pat.rs

@@ -6,7 +6,7 @@
 /// ```
 #[macro_export]
 #[rustc_builtin_macro(pattern_type)]
-#[unstable(feature = "core_pattern_type", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 macro_rules! pattern_type {
     ($($arg:tt)*) => {
         /* compiler built-in */

std/src/lib.rs

@@ -589,7 +589,7 @@ pub mod net;
 pub mod num;
 pub mod os;
 pub mod panic;
-#[unstable(feature = "core_pattern_types", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 pub mod pat;
 pub mod path;
 #[unstable(feature = "anonymous_pipe", issue = "127154")]