Manual pages: Standardize on CONFORMING TO as section title

There is quite some value (in terms of readability and user
expectations) if consistent names are used for the sections
within manual pages. This patch is one of a series to bring
about this consistency.

Currently we have STANDARDS (3) or CONFORMING TO (6).
Let's standardize on the latter (which is also what is
suggested in man-pages(7)).

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

misc-utils/logger.1

@@ -355,7 +355,7 @@ For the priority order and intended purposes of these facilities and levels, see
 .BR journalctl (1),
 .BR syslog (3),
 .BR systemd.journal-fields (7)
-.SH STANDARDS
+.SH CONFORMING TO
 The
 .B logger
 command is expected to be IEEE Std 1003.2 ("POSIX.2") compatible.

text-utils/col.1

@@ -141,7 +141,7 @@ will display a warning message.
 .BR expand (1),
 .BR nroff (1),
 .BR tbl (1)
-.SH STANDARDS
+.SH CONFORMING TO
 The
 .B col
 utility conforms to the Single UNIX Specification, Version 2.  The

text-utils/hexdump.1

@@ -369,7 +369,7 @@ Implicit coloring can be disabled by an empty file \fI/etc/terminal-colors.d/hex
 See
 .BR terminal-colors.d (5)
 for more details about colorization configuration.
-.SH STANDARDS
+.SH CONFORMING TO
 The
 .B hexdump
 utility is expected to be IEEE Std 1003.2 ("POSIX.2") compatible.