ARM: dts: msm: Do not specify card detect gpio for 8939 SKUK

according to hw, card detect gpio should not be specified.
Mark the slot as non-removeable as well so that polling will
not be enabled unnecessarily.

Change-Id: I51b4d252cfafaac88abc448fca58fbbb5bac6b46
Signed-off-by: Guoping Yu <guopingy@codeaurora.org>