scftorture: Make torture_type static

Fix the 'make C=1' warning:
kernel/scftorture.c:71:6: warning: symbol 'torture_type' was not declared. Should it be static?
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

kernel/scftorture.c

@@ -68,7 +68,7 @@ torture_param(int, weight_many_wait, -1, "Testing weight for multi-CPU operation
 torture_param(int, weight_all, -1, "Testing weight for all-CPU no-wait operations.");
 torture_param(int, weight_all_wait, -1, "Testing weight for all-CPU operations.");
 
-char *torture_type = "";
+static char *torture_type = "";
 
 #ifdef MODULE
 # define SCFTORT_SHUTDOWN 0