sched: Add snapshot of Window Assisted Load Tracking (WALT)

This snapshot is taken from msm-4.14 as of
commit 871eac76e6be567 ("sched: Improve the scheduler").

Change-Id: Ib4e0b39526d3009cedebb626ece5a767d8247846
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>
diff --git a/init/Kconfig b/init/Kconfig
index 86ce094..a572df9 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -420,6 +420,15 @@
 
 	  If in doubt, say N here.
 
+config SCHED_WALT
+	bool "Support window based load tracking"
+	depends on SMP
+	help
+	This feature will allow the scheduler to maintain a tunable window
+	based set of metrics for tasks and runqueues. These metrics can be
+	used to guide task placement as well as task frequency requirements
+	for cpufreq governors.
+
 config BSD_PROCESS_ACCT
 	bool "BSD Process Accounting"
 	depends on MULTIUSER