typo in mount.2

[Markus Friedl <markus.friedl@informatik.uni-erlangen.de>]

hello!
mount.2 speaks about umount(2) instead of unmount(2)

--- /src/lib/libc/sys/mount.2	Sun Feb 28 05:19:24 1999
+++ /tmp/mount.2	Fri Mar  5 09:41:01 1999
@@ -161,7 +161,7 @@
 .Ed
 .Pp
 The
-.Fn umount
+.Fn unmount
 function call disassociates the filesystem from the specified
 mount point
 .Fa dir .
@@ -183,8 +183,8 @@
 .Va errno
 is set to indicate the error.
 .Pp
-.Nm umount
-returns the value 0 if the umount succeeded; otherwise -1 is returned
+.Fn unmount
+returns the value 0 if the unmount succeeded; otherwise -1 is returned
 and the variable
 .Va errno
 is set to indicate the error.
@@ -293,7 +293,7 @@
 points outside the process's allocated address space.
 .El
 .Pp
-.Nm umount
+.Fn umount
 may fail with one of the following errors:
 .Bl -tag -width [ENAMETOOLONG]
 .It Bq Er EPERM
@@ -337,6 +337,6 @@
 .Sh HISTORY
 .Fn mount
 and
-.Fn umount
+.Fn unmount
 function calls appeared in
 .At v6 .