pm-qa: collecting seperated test switches into one central file.

It is inconvenient for user to edit these seperated switches, so move them into
one central file.

Signed-off-by: Hongbo Zhang <hongbo.zhang@linaro.org>
diff --git a/thermal/thermal_06.sh b/thermal/thermal_06.sh
index 28fdaec..0084281 100755
--- a/thermal/thermal_06.sh
+++ b/thermal/thermal_06.sh
@@ -28,9 +28,7 @@
 source ../include/functions.sh
 source ../include/thermal_functions.sh
 
-# test_switch: switch on/off this test
-test_switch=0
-if [ "$test_switch" -eq 0 ]; then
+if [ "$thermal_try_max" -eq 0 ]; then
     log_skip "test of trip points being crossed"
     exit 0
 fi