staging: staging: kpc2000: kpc_dma: fix symbol 'kpc_dma_add_device' was not declared.

This was reported by sparse:
drivers/staging/kpc2000/kpc_dma/kpc_dma_driver.c:39:7: warning: symbol 'kpc_dma_add_device
' was not declared. Should it be static?
Signed-off-by: Valerio Genovese <valerio.click@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/kpc2000/kpc_dma/kpc_dma_driver.c

@@ -36,7 +36,7 @@ struct kpc_dma_device *kpc_dma_lookup_device(int minor)
 	return c;
 }
 
-void  kpc_dma_add_device(struct kpc_dma_device *ldev)
+static void kpc_dma_add_device(struct kpc_dma_device *ldev)
 {
 	mutex_lock(&kpc_dma_mtx);
 	list_add(&ldev->list, &kpc_dma_list);