dtlk: add missing MODULE_DESCRIPTION() macro

With ARCH=m68k, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/char/dtlk.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/20240617-md-m68k-drivers-char-dtlk-v1-1-a53a237f1f06@quicinc.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/char/dtlk.c

@@ -660,4 +660,5 @@ static char dtlk_write_tts(char ch)
 	return 0;
 }
 
+MODULE_DESCRIPTION("RC Systems DoubleTalk PC speech card driver");
 MODULE_LICENSE("GPL");