[PATCH] rust: str: make NullTerminatedFormatter public

[Alexandre Courbot]

If `CONFIG_BLOCK` is disabled, the following warnings are displayed
during build:

  warning: struct `NullTerminatedFormatter` is never constructed
    --> ../rust/kernel/str.rs:667:19
      |
  667 | pub(crate) struct NullTerminatedFormatter<'a> {
      |                   ^^^^^^^^^^^^^^^^^^^^^^^
      |
      = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default

  warning: associated function `new` is never used
    --> ../rust/kernel/str.rs:673:19
      |
  671 | impl<'a> NullTerminatedFormatter<'a> {
      | ------------------------------------ associated function in this implementation
  672 |     /// Create a new [`Self`] instance.
  673 |     pub(crate) fn new(buffer: &'a mut [u8]) -> Option<NullTerminatedFormatter<'a>> {

Fix them by making `NullTerminatedFormatter` public, as it could be
useful for drivers anyway.

Fixes: cdde7a1951ff ("rust: str: introduce `NullTerminatedFormatter`")
Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
---
 rust/kernel/str.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index fa87779d2253..3f8918764640 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -664,13 +664,13 @@ fn write_str(&mut self, s: &str) -> fmt::Result {
 ///
 /// * The first byte of `buffer` is always zero.
 /// * The length of `buffer` is at least 1.
-pub(crate) struct NullTerminatedFormatter<'a> {
+pub struct NullTerminatedFormatter<'a> {
     buffer: &'a mut [u8],
 }
 
 impl<'a> NullTerminatedFormatter<'a> {
     /// Create a new [`Self`] instance.
-    pub(crate) fn new(buffer: &'a mut [u8]) -> Option<NullTerminatedFormatter<'a>> {
+    pub fn new(buffer: &'a mut [u8]) -> Option<NullTerminatedFormatter<'a>> {
         *(buffer.first_mut()?) = 0;
 
         // INVARIANT:

---
base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
change-id: 20260224-nullterminatedformatter-d06c3733c3bc

Best regards,
-- 
Alexandre Courbot <acourbot@xxxxxxxxxx>