Manual pages: Standardize on EXIT STATUS 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 EXIT STATUS (18), EXIT CODES (3), RETURN CODE (7),
RETURN CODES (1), or RETURN VALUE (4 instances in pages that document
commands, rather than functions).

Let's standardize on the EXIT STATUS (which is also what is
suggested in man-pages(7), and is the POSIX terminology).

A subsequent patch will clean up corresponding miswordings in
manual page text.

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

disk-utils/fsck.minix.8

@@ -92,7 +92,7 @@ will print "unable to read super block".  If the device exists, but is not
 a MINIX filesystem,
 .B fsck.minix
 will print "bad magic number in super-block".
-.SH EXIT CODES
+.SH EXIT STATUS
 The exit code returned by
 .B fsck.minix
 is the sum of the following:

disk-utils/mkfs.bfs.8

@@ -47,7 +47,7 @@ Option
 only works as
 .B \-\-version
 when it is the only option.
-.SH EXIT CODES
+.SH EXIT STATUS
 The exit code returned by
 .B mkfs.bfs
 is 0 when all went well, and 1 when something went wrong.

disk-utils/mkfs.minix.8

@@ -70,7 +70,7 @@ with other options.
 .TP
 \fB\-h\fR, \fB\-\-help\fR
 Display help text and exit.
-.SH EXIT CODES
+.SH EXIT STATUS
 The exit code returned by
 .B mkfs.minix
 is one of the following:

misc-utils/blkid.8

@@ -286,7 +286,7 @@ Look up the device that uses this filesystem \fIuuid\fR.  For more details see t
 .TP
 \fB\-V\fR, \fB\-\-version\fR
 Display version number and exit.
-.SH RETURN CODE
+.SH EXIT STATUS
 If the specified device or device addressed by specified token (option
 \fB\-\-match\-token\fR) was found and it's possible to gather any information about the
 device, an exit code 0 is returned.  Note the option \fB\-\-match\-tag\fR filters output

misc-utils/kill.1

@@ -171,7 +171,7 @@ preferred in relation to the
 executable described by this manual.  Easiest way to ensure one is executing
 the executable is to use full path when calling the command, for example:
 .B "/bin/kill \-\-version"
-.SH RETURN CODES
+.SH EXIT STATUS
 .B kill
 has the following return codes:
 .PP

misc-utils/logger.1

@@ -294,7 +294,7 @@ Display version information and exit.
 .TP
 .BR \-h , " \-\-help"
 Display help text and exit.
-.SH RETURN VALUE
+.SH EXIT STATUS
 The
 .B logger
 utility exits 0 on success, and >0 if an error occurs.

misc-utils/lsblk.8

@@ -180,7 +180,7 @@ This sysfs block directory appeared in kernel 2.6.27 (October 2008).
 In case of problems with a new enough kernel, check that CONFIG_SYSFS
 was enabled at the time of the kernel build.
 
-.SH RETURN CODES
+.SH EXIT STATUS
 .IP 0
 success
 .IP 1

sys-utils/chcpu.8

@@ -77,7 +77,7 @@ Display version information and exit.
 .BR \-h , " \-\-help"
 Display help text and exit.
 
-.SH RETURN CODES
+.SH EXIT STATUS
 .B chcpu
 has the following return codes:
 .TP

sys-utils/chmem.8

@@ -79,7 +79,7 @@ progress.
 .TP
 .BR \-V ", " \-\-version
 Print the version number, then exit.
-.SH RETURN CODES
+.SH EXIT STATUS
 .B chmem
 has the following return codes:
 .TP

sys-utils/fstrim.8

@@ -115,7 +115,7 @@ Display version information and exit.
 .BR \-h , " \-\-help"
 Display help text and exit.
 
-.SH RETURN CODES
+.SH EXIT STATUS
 .IP 0
 success
 .IP 1

sys-utils/losetup.8

@@ -170,7 +170,7 @@ Display help text and exit.
 .B Cryptoloop is no longer supported in favor of dm-crypt.
 .B For more details see cryptsetup(8).
 
-.SH RETURN VALUE
+.SH EXIT STATUS
 .B losetup
 returns 0 on success, nonzero on failure.  When
 .B losetup

sys-utils/mount.8

@@ -2501,7 +2501,7 @@ initialize a new device if the same backing file is already used for some loop
 device with the same offset and sizelimit. This is necessary to avoid
 a filesystem corruption.
 
-.SH RETURN CODES
+.SH EXIT STATUS
 .B mount
 has the following return codes (the bits can be ORed):
 .TP

sys-utils/switch_root.8

@@ -28,7 +28,7 @@ Display help text and exit.
 .IP "\fB\-V, \-\-version\fP"
 Display version information and exit.
 
-.SH RETURN VALUE
+.SH EXIT STATUS
 .B switch_root
 returns 0 on success and 1 on failure.
 

sys-utils/zramctl.8

@@ -95,7 +95,7 @@ Display version information and exit.
 .BR \-h , " \-\-help"
 Display help text and exit.
 
-.SH RETURN VALUE
+.SH EXIT STATUS
 .B zramctl
 returns 0 on success, nonzero on failure.