rust: lib: Rust 1.77 compat fixes

Signed-off-by: Janne Grunau <j@jannau.net>

Author: jannau

rust/alloc/lib.rs

@@ -106,7 +106,7 @@
 #![feature(allocator_api)]
 #![feature(array_chunks)]
 #![feature(array_into_iter_constructors)]
-#![feature(array_methods)]
+#![cfg_attr(not(version("1.77")), feature(array_methods))]
 #![feature(array_windows)]
 #![feature(ascii_char)]
 #![feature(assert_matches)]
@@ -124,7 +124,7 @@
 #![feature(const_size_of_val)]
 #![feature(const_waker)]
 #![feature(core_intrinsics)]
-#![feature(core_panic)]
+#![cfg_attr(not(version("1.77")), feature(core_panic))]
 #![feature(deprecated_suggestion)]
 #![feature(dispatch_from_dyn)]
 #![feature(error_generic_member_access)]
@@ -151,7 +151,7 @@
 #![feature(set_ptr_value)]
 #![feature(sized_type_properties)]
 #![feature(slice_from_ptr_range)]
-#![feature(slice_group_by)]
+#![cfg_attr(not(version("1.77")), feature(slice_group_by))]
 #![feature(slice_ptr_get)]
 #![feature(slice_ptr_len)]
 #![feature(slice_range)]