Add some missing names to the NAME sections.

For inet(3), go the other way, remove some bogus symlinks.
Found while testing the new makewhatis(8).
ok jmc@

src/lib/libc/stdlib/rand.3

@@ -29,13 +29,14 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"	$OpenBSD: rand.3,v 1.14 2014/01/21 03:15:45 schwarze Exp $
+.\"	$OpenBSD: rand.3,v 1.15 2014/04/07 17:57:56 schwarze Exp $
 .\"
-.Dd $Mdocdate: January 21 2014 $
+.Dd $Mdocdate: April 7 2014 $
 .Dt RAND 3
 .Os
 .Sh NAME
 .Nm rand ,
+.Nm rand_r ,
 .Nm srand
 .Nd bad random number generator
 .Sh SYNOPSIS

src/lib/libc/string/memchr.3

@@ -1,4 +1,4 @@
-.\"	$OpenBSD: memchr.3,v 1.11 2013/06/05 03:39:23 tedu Exp $
+.\"	$OpenBSD: memchr.3,v 1.12 2014/04/07 17:57:56 schwarze Exp $
 .\"
 .\" Copyright (c) 1990, 1991 The Regents of the University of California.
 .\" All rights reserved.
@@ -31,11 +31,12 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: June 5 2013 $
+.Dd $Mdocdate: April 7 2014 $
 .Dt MEMCHR 3
 .Os
 .Sh NAME
-.Nm memchr
+.Nm memchr ,
+.Nm memrchr
 .Nd locate byte in byte string
 .Sh SYNOPSIS
 .In string.h

src/lib/libc/string/strerror.3

@@ -29,13 +29,14 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"	$OpenBSD: strerror.3,v 1.12 2013/06/05 03:39:23 tedu Exp $
+.\"	$OpenBSD: strerror.3,v 1.13 2014/04/07 17:57:56 schwarze Exp $
 .\"
-.Dd $Mdocdate: June 5 2013 $
+.Dd $Mdocdate: April 7 2014 $
 .Dt STRERROR 3
 .Os
 .Sh NAME
-.Nm strerror
+.Nm strerror ,
+.Nm strerror_r
 .Nd get error message string
 .Sh SYNOPSIS
 .In string.h