ARM: dts: omap4-sdp: Fix pin muxing for wl12xx

Mux mode for wlan/sdmmc5 should be MODE0 in pinmux_wl12xx_pins and
Enable Pull up on sdmmc5_clk to detect SDIO card.

This fixes WLAN on omap4-sdp that got broken in v3.10 when we
moved omap4 to boot using device tree only as I did not have
the WL12XX card in my omap4 SDP to test with. The commit that
attempted to make WL12XX working on omap4 SDP was 775d2418


(ARM: dts: Fix muxing and regulator for wl12xx on the SDIO
bus for blaze).

Signed-off-by: Balaji T K <balajitk@ti.com>
[tony@atomide.com: updated comments for the regression]
Signed-off-by: Tony Lindgren <tony@atomide.com>