KUnit: add missing MODULE_DESCRIPTION() macros for lib/test_*.ko

make allmodconfig && make W=1 C=1 reports for lib/test_*.ko:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_hexdump.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_dhry.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_firmware.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_sysctl.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_hash.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_ida.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_list_sort.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_min_heap.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_module.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_sort.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_static_keys.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_static_key_base.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_memcat_p.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_blackhole_dev.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_meminit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_free_pages.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_kprobes.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_ref_tracker.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_bits.o

Add the missing invocations of the MODULE_DESCRIPTION() macro.

Link: https://lkml.kernel.org/r/20240619-md-lib-test-v2-1-301e30eeba1e@quicinc.com


Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>