kunit/fortify: add missing MODULE_DESCRIPTION() macros

kunit/fortify: add missing MODULE_DESCRIPTION() macros

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/memcpy_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/fortify_kunit.o

Add the missing invocations of the MODULE_DESCRIPTION() macro.

Link: https://lkml.kernel.org/r/20240531-md-lib-fortify_source-v1-1-2c37f7fbaafc@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>