Improve the description of locale dependency:

* mention LC_COLLATE;
* clarify that all these functions are infested, including the *_l() versions;
* avoid ENVIRONMENT, these functions don't inspect it;
* and point to the C library functions that change the locale.
OK millert@

src/lib/libc/string/strcoll.3

@@ -1,4 +1,4 @@
-.\"	$OpenBSD: strcoll.3,v 1.10 2017/09/05 03:16:13 schwarze Exp $
+.\"	$OpenBSD: strcoll.3,v 1.11 2019/01/18 07:43:36 schwarze Exp $
 .\"
 .\" Copyright (c) 1990, 1991 The Regents of the University of California.
 .\" Copyright (c) 2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -32,7 +32,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: September 5 2017 $
+.Dd $Mdocdate: January 18 2019 $
 .Dt STRCOLL 3
 .Os
 .Sh NAME
@@ -68,12 +68,15 @@ they have the same effect as
 and the global locale, the thread-specific locale, and the
 .Fa locale
 argument are ignored.
-.Sh ENVIRONMENT
-On other operating systems, the behaviour of
-.Fn strcoll
-may depend on the
+On other operating systems, results may depend on the
 .Dv LC_CTYPE
-.Xr locale 1 .
+and
+.Dv LC_COLLATE
+locale categories set with
+.Xr setlocale 3 ,
+.Xr uselocale 3 ,
+or
+.Xr newlocale 3 .
 .Sh SEE ALSO
 .Xr newlocale 3 ,
 .Xr setlocale 3 ,

src/lib/libc/string/strxfrm.3

@@ -1,4 +1,4 @@
-.\"	$OpenBSD: strxfrm.3,v 1.11 2017/09/05 03:16:13 schwarze Exp $
+.\"	$OpenBSD: strxfrm.3,v 1.12 2019/01/18 07:43:36 schwarze Exp $
 .\"
 .\" Copyright (c) 1990, 1991 The Regents of the University of California.
 .\" Copyright (c) 2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -32,7 +32,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: September 5 2017 $
+.Dd $Mdocdate: January 18 2019 $
 .Dt STRXFRM 3
 .Os
 .Sh NAME
@@ -69,12 +69,15 @@ both have the same effect as
 and the global locale, the thread-specific locale, and the
 .Fa locale
 argument are ignored.
-.Sh ENVIRONMENT
-On other operating systems, the behaviour of
-.Fn strxfrm
-may depend on the
+On other operating systems, the behaviour may depend on the
 .Dv LC_CTYPE
-.Xr locale 1 .
+and
+.Dv LC_COLLATE
+locale categories set with
+.Xr setlocale 3 ,
+.Xr uselocale 3 ,
+or
+.Xr newlocale 3 .
 .Sh SEE ALSO
 .Xr newlocale 3 ,
 .Xr setlocale 3 ,