rust: fix signature of rust_fmt_argument

Without this change, the rest of this series will emit the following
error message:

error[E0308]: `if` and `else` have incompatible types
  --> <linux>/rust/kernel/print.rs:22:22
   |
21 | #[export]
   | --------- expected because of this
22 | unsafe extern "C" fn rust_fmt_argument(
   |                      ^^^^^^^^^^^^^^^^^ expected `u8`, found `i8`
   |
   = note: expected fn item `unsafe extern "C" fn(*mut u8, *mut u8, *mut c_void) -> *mut u8 {bindings::rust_fmt_argument}`
              found fn item `unsafe extern "C" fn(*mut i8, *mut i8, *const c_void) -> *mut i8 {print::rust_fmt_argument}`

The error may be different depending on the architecture.

To fix this, change the void pointer argument to use a const pointer,
and change the imports to use crate::ffi instead of core::ffi for
integer types.

Fixes: 787983da7718 ("vsprintf: add new `%pA` format specifier")
Reviewed-by: Tamir Duberstein <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Alice Ryhl <[email protected]>
Acked-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 56fe96319292..a8ac4c4fffcf 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -2285,7 +2285,7 @@ int __init no_hash_pointers_enable(char *str)
 early_param("no_hash_pointers", no_hash_pointers_enable);
 
 /* Used for Rust formatting ('%pA'). */
-char *rust_fmt_argument(char *buf, char *end, void *ptr);
+char *rust_fmt_argument(char *buf, char *end, const void *ptr);
 
 /*
  * Show a '%p' thing.  A kernel extension is that the '%p' is followed