kfifo: drop __kfifo_dma_out_finish_r()

It is the same as __kfifo_skip_r(), so:
* drop __kfifo_dma_out_finish_r() completely, and
* replace its (only) use by __kfifo_skip_r().

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20240405060826.2521-2-jirislaby@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>