s390/dma: do not call debug_dma after free

In dma_free_coherent call debug_dma_free_coherent before deallocating
the memory to avoid a possible use after free.

Reviewed-by: Gerald Schaefer <[e-mail]>
Signed-off-by: Sebastian Ott <[e-mail]>
Signed-off-by: Martin Schwidefsky <[e-mail]>

arch/s390/include/asm/dma-mapping.h

···
 {
 	struct dma_map_ops *dma_ops = get_dma_ops(dev);
 
-	dma_ops->free(dev, size, cpu_addr, dma_handle, NULL);
 	debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
+	dma_ops->free(dev, size, cpu_addr, dma_handle, NULL);
 }
 
 #endif /* _ASM_S390_DMA_MAPPING_H */