samples: configfs: add missing MODULE_DESCRIPTION() macro

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/configfs/configfs_sample.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Nacked-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240601-md-samples-configfs-v1-1-83ef2d3c0088@quicinc.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

samples/configfs/configfs_sample.c

@@ -364,4 +364,5 @@ static void __exit configfs_example_exit(void)
 
 module_init(configfs_example_init);
 module_exit(configfs_example_exit);
+MODULE_DESCRIPTION("Sample configfs module");
 MODULE_LICENSE("GPL");