test feature supported before running suite

add a basic sanity file which will check for feature support and
will proceed only if feature supported

Signed-off-by: Sanjay Singh Rawat <sanjay.rawat@linaro.org>
diff --git a/cpufreq/cpufreq_sanity.txt b/cpufreq/cpufreq_sanity.txt
new file mode 100644
index 0000000..bee26be
--- /dev/null
+++ b/cpufreq/cpufreq_sanity.txt
@@ -0,0 +1 @@
+cpufreq is not supported or not the root user. Skipping all cpufreq tests...