sysupgrade: clarify online help

Fixes #12346.

Signed-off-by: Paul Fertser <fercerpav@gmail.com>

SVN-Revision: 34975

package/base-files/files/sbin/sysupgrade

@@ -47,27 +47,30 @@ export ARGC="$#"
 
 [ -z "$ARGV" -a -z "$NEED_IMAGE" -o $HELP -gt 0 ] && {
 	cat <<EOF
-Usage: $0 [options] <image file or URL>
+Usage: $0 [<upgrade-option>...] <image file or URL>
+       $0 [-q] [-i] <backup-command> <file>
 
-Options:
+upgrade-option:
 	-d <delay>   add a delay before rebooting
 	-f <config>  restore configuration from .tar.gz (file or url)
 	-i           interactive mode
 	-c           attempt to preserve all changed files in /etc/
-	-b / --create-backup <file>
-	             create .tar.gz of files specified in sysupgrade.conf
-	             then exit. Does not flash an image. If file is '-',
-	             i.e. stdout, verbosity is set to 0 (i.e. quiet).
-	-r / --restore-backup <file>
-	             restore a .tar.gz created with sysupgrade -b
-	             then exit. Does not flash an image. If file is '-',
-	             the archive is read from stdin.
 	-n           do not save configuration over reflash
-	-F / --force
+	-F | --force
 	             Flash image even if image checks fail, this is dangerous!
 	-q           less verbose
 	-v           more verbose
-	-h / --help  display this help
+	-h | --help  display this help
+
+backup-command:
+	-b | --create-backup <file>
+	             create .tar.gz of files specified in sysupgrade.conf
+	             then exit. Does not flash an image. If file is '-',
+	             i.e. stdout, verbosity is set to 0 (i.e. quiet).
+	-r | --restore-backup <file>
+	             restore a .tar.gz created with sysupgrade -b
+	             then exit. Does not flash an image. If file is '-',
+	             the archive is read from stdin.
 
 EOF
 	exit 1
@@ -75,8 +78,8 @@ EOF
 
 [ -n "$ARGV" -a -n "$NEED_IMAGE" ] && {
 	cat <<-EOF
-		-b/--create-backup and -r/--restore-backup do not perform a firmware upgrade.
-		Do not specify both -b/-r and a firmware image.
+		-b|--create-backup and -r|--restore-backup do not perform a firmware upgrade.
+		Do not specify both -b|-r and a firmware image.
 	EOF
 	exit 1
 }