mkfs: remove a pointless rtfreesp_init forward declaration

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff --git a/mkfs/proto.c b/mkfs/proto.c
index 0601098..9d21f02 100644
--- a/mkfs/proto.c
+++ b/mkfs/proto.c
@@ -18,7 +18,6 @@
 static void rsvfile(xfs_mount_t *mp, xfs_inode_t *ip, long long len);
 static char *newregfile(char **pp, int *len);
 static void rtinit(xfs_mount_t *mp);
-static void rtfreesp_init(struct xfs_mount *mp);
 static long filesize(int fd);
 static int slashes_are_spaces;