mmc: tmio: remove SDIO from TODO list

We surely have SDIO support by now :)
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/tmio_mmc_pio.c

@@ -22,7 +22,6 @@
  * TODO:
  *   Investigate using a workqueue for PIO transfers
  *   Eliminate FIXMEs
- *   SDIO support
  *   Better Power management
  *   Handle MMC errors better
  *   double buffer support