platform/chrome: cros_ec_proto: add missing MODULE_DESCRIPTION() macro

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/platform/chrome/cros_kunit_proto_test.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240610-md-drivers-platform-chrome-v1-1-f9c75adcc1ca@quicinc.comSigned-off-by: Tzung-Bi Shih <tzungbi@kernel.org>

drivers/platform/chrome/cros_ec_proto_test.c

@@ -2740,4 +2740,5 @@ static struct kunit_suite cros_ec_proto_test_suite = {
 
 kunit_test_suite(cros_ec_proto_test_suite);
 
+MODULE_DESCRIPTION("Kunit tests for ChromeOS Embedded Controller protocol");
 MODULE_LICENSE("GPL");