net: wireless: ti: wl1251 add device tree support

We will have the wl1251 defined as a child node of the mmc interface
and can read setup for gpios, interrupts and the ti,use-eeprom
property from there instead of pdata to be provided by pdata-quirks.

Fixes: 81eef6ca ("mmc: omap_hsmmc: Use dma_request_chan() for requesting DMA channel")
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Cc: <stable@vger.kernel.org> # v4.7+
[Ulf: Fixed up some complaints from checkpatch]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>