splice: remove duplicate noinline from pipe_clear_nowait

pipe_clear_nowait has two noinline macros, but we only need one.

I checked the whole tree, and this is the only occurrence:

$ grep -r "noinline .* noinline"
fs/splice.c:static noinline void noinline pipe_clear_nowait(struct file *file)
$

Fixes: 0f99fc5 ("splice: clear FMODE_NOWAIT on file if splice/vmsplice is used")
Signed-off-by: "T.J. Mercier" <tjmercier@google.com>
Link: https://lore.kernel.org/20250423180025.2627670-1-tjmercier@google.com
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: tweej

fs/splice.c

@@ -45,7 +45,7 @@
  * here if set to avoid blocking other users of this pipe if splice is
  * being done on it.
  */
-static noinline void noinline pipe_clear_nowait(struct file *file)
+static noinline void pipe_clear_nowait(struct file *file)
 {
 	fmode_t fmode = READ_ONCE(file->f_mode);