ARM: dts: msm: Do not specify card detect gpio for QRD8926 SKUG

SD card cannot be removed or inserted without removing the battery
on 8926 SKUG and hence card detect gpio should not be specified for
this type of board. Also, mark the slot as non-removable so that
polling will not be enabled unnecessarily.

Change-Id: I0e13fed66afa6ba00ed59b83fb4da429693829b8
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>