clk: test: add missing MODULE_DESCRIPTION() macros

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/clk/clk_test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/clk/clk-gate_test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/clk/clk-fractional-divider_test.o

Add the missing invocations of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240602-md-clk-test-v1-1-a6afd4793337@quicinc.com
[sboyd@kernel.org: Reword header and description]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/clk-fractional-divider_test.c

 // SPDX-License-Identifier: GPL-2.0
 /*
- * Kunit test for clock fractional divider
+ * Kunit tests for clk fractional divider
  */
 #include <linux/clk-provider.h>
 #include <kunit/test.h>
@@ -144,4 +144,5 @@ static struct kunit_suite clk_fd_approximation_suite = {
 kunit_test_suites(
 	&clk_fd_approximation_suite
 );
+MODULE_DESCRIPTION("Kunit tests for clk fractional divider");
 MODULE_LICENSE("GPL");

drivers/clk/clk-gate_test.c

 // SPDX-License-Identifier: GPL-2.0
 /*
- * Kunit test for clk gate basic type
+ * Kunit tests for clk gate
  */
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
@@ -461,4 +461,5 @@ kunit_test_suites(
 	&clk_gate_test_hiword_suite,
 	&clk_gate_test_enabled_suite
 );
+MODULE_DESCRIPTION("Kunit tests for clk gate");
 MODULE_LICENSE("GPL v2");

drivers/clk/clk_test.c

 // SPDX-License-Identifier: GPL-2.0
 /*
- * Kunit test for clk rate management
+ * Kunit tests for clk framework
  */
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
@@ -2674,4 +2674,5 @@ kunit_test_suites(
 	&clk_single_parent_mux_test_suite,
 	&clk_uncached_test_suite
 );
+MODULE_DESCRIPTION("Kunit tests for clk framework");
 MODULE_LICENSE("GPL v2");