rust: macros: replace kernel::c_str! with C-Strings

C-String literals were added in Rust 1.77. Replace instances of
`kernel::c_str!` with C-String literals where possible.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://patch.msgid.link/20251113-core-cstr-cstrings-v3-6-411b34002774@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: tamird

rust/macros/module.rs

@@ -228,7 +228,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
             type LocalModule = {type_};
 
             impl ::kernel::ModuleMetadata for {type_} {{
-                const NAME: &'static ::kernel::str::CStr = ::kernel::c_str!(\"{name}\");
+                const NAME: &'static ::kernel::str::CStr = c\"{name}\";
             }}
 
             // Double nested modules, since then nobody can access the public items inside.