dma: kmsan: export kmsan_handle_dma() for modules

commit 19fac3c upstream.

kmsan_handle_dma() is used by virtio_ring() which can be built as a
module.  kmsan_handle_dma() needs to be exported otherwise building the
virtio_ring fails.

Export kmsan_handle_dma for modules.

Link: https://lkml.kernel.org/r/20250218091411.MMS3wBN9@linutronix.de
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502150634.qjxwSeJR-lkp@intel.com/
Fixes: 7ade4f1 ("dma: kmsan: unpoison DMA mappings")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Macro Elver <elver@google.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Sebastian Andrzej Siewior

mm/kmsan/hooks.c

@@ -357,6 +357,7 @@ void kmsan_handle_dma(struct page *page, size_t offset, size_t size,
 		size -= to_go;
 	}
 }
+EXPORT_SYMBOL_GPL(kmsan_handle_dma);
 
 void kmsan_handle_dma_sg(struct scatterlist *sg, int nents,
 			 enum dma_data_direction dir)