spi: fix a typo inside a kernel-doc markup

spi_split_tranfers_maxsize -> spi_split_transfers_maxsize
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/a103f4f48735caa1a09fad94c5d76e73e2ce37b8.1603469755.git.mchehab+huawei@kernel.orgSigned-off-by: NMark Brown <broonie@kernel.org>

drivers/spi/spi.c

@@ -3193,7 +3193,7 @@ static int __spi_split_transfer_maxsize(struct spi_controller *ctlr,
 }
 
 /**
- * spi_split_tranfers_maxsize - split spi transfers into multiple transfers
+ * spi_split_transfers_maxsize - split spi transfers into multiple transfers
  *                               when an individual transfer exceeds a
  *                               certain size
  * @ctlr:    the @spi_controller for this transfer