Initializes the s variable

(cherry picked from commit 307d5d5d)

matlab/kalman/likelihood/missing_observations_kalman_filter.m

@@ -83,7 +83,8 @@ LIK  = Inf;                % Default value of the log likelihood.
 oldK = Inf;
 notsteady   = 1;
 F_singular  = 1;
-    
+s = 0;
+
 while notsteady & t<=last
     s  = t-start+1;
     d_index = data_index{t};

matlab/kalman/likelihood/missing_observations_kalman_filter_d.m

@@ -70,6 +70,7 @@ oldK = Inf;
 if isequal(H,0)
     H = zeros(pp,pp);
 end
+s = 0;
 
 while rank(Pinf,kalman_tol) && (t<=last)
     s = t-start+1;