ARM: dts: msm: Reduce the clocks for SD card slot for MSM8610

The SD cards functionality on QRD devices are failing
with CRC errors when used with higher clock / bus modes.

So reduce the clock speed for SD card slot.

CRs-Fixed:  491789
Change-Id: I07df5bcab12579d4db287913f7e082441bac7e6d
Signed-off-by: Pratibhasagar V <pratibha@codeaurora.org>