fs: nfs: add missing MODULE_DESCRIPTION() macros

Fix the 'make W=1' warnings:
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs_common/nfs_acl.o
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs_common/grace.o
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs/nfs.o
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs/nfsv2.o
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs/nfsv3.o
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/nfs/nfsv4.o
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/inode.c

@@ -2539,6 +2539,7 @@ static void __exit exit_nfs_fs(void)
 
 /* Not quite true; I just maintain it */
 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
+MODULE_DESCRIPTION("NFS client support");
 MODULE_LICENSE("GPL");
 module_param(enable_ino64, bool, 0644);
 

fs/nfs/nfs2super.c

@@ -26,6 +26,7 @@ static void __exit exit_nfs_v2(void)
 	unregister_nfs_version(&nfs_v2);
 }
 
+MODULE_DESCRIPTION("NFSv2 client support");
 MODULE_LICENSE("GPL");
 
 module_init(init_nfs_v2);

fs/nfs/nfs3super.c

@@ -27,6 +27,7 @@ static void __exit exit_nfs_v3(void)
 	unregister_nfs_version(&nfs_v3);
 }
 
+MODULE_DESCRIPTION("NFSv3 client support");
 MODULE_LICENSE("GPL");
 
 module_init(init_nfs_v3);

fs/nfs/nfs4super.c

@@ -332,6 +332,7 @@ static void __exit exit_nfs_v4(void)
 	nfs_dns_resolver_destroy();
 }
 
+MODULE_DESCRIPTION("NFSv4 client support");
 MODULE_LICENSE("GPL");
 
 module_init(init_nfs_v4);

fs/nfs_common/grace.c

@@ -139,6 +139,7 @@ exit_grace(void)
 }
 
 MODULE_AUTHOR("Jeff Layton <jlayton@primarydata.com>");
+MODULE_DESCRIPTION("NFS client and server infrastructure");
 MODULE_LICENSE("GPL");
 module_init(init_grace)
 module_exit(exit_grace)

fs/nfs_common/nfsacl.c

@@ -29,6 +29,7 @@
 #include <linux/nfs3.h>
 #include <linux/sort.h>
 
+MODULE_DESCRIPTION("NFS ACL support");
 MODULE_LICENSE("GPL");
 
 struct nfsacl_encode_desc {