msm: Config option to enable idle stats device

MSM_SLEEP_STATS_DEVICE option is used to compile idle stats device
framework which is needed for GPU DCVS feature.

Change-Id: I9550c90054587aa4fcec40131761eeaf54da8a03
Signed-off-by: Lynus Vaz <lvaz@codeaurora.org>
diff --git a/arch/arm/mach-msm/Kconfig b/arch/arm/mach-msm/Kconfig
index ee9b2de..9df90cd 100644
--- a/arch/arm/mach-msm/Kconfig
+++ b/arch/arm/mach-msm/Kconfig
@@ -1845,6 +1845,9 @@
 	depends on CPU_IDLE
 	default n
 
+config MSM_SLEEP_STATS_DEVICE
+	bool "Enable exporting of MSM sleep device stats to userspace"
+
 config MSM_STANDALONE_POWER_COLLAPSE
        bool "Enable standalone power collapse"
        default n