distr_info: add long option --service-manager, fix print info formatting

bin/distr_info

@@ -6,7 +6,7 @@
 # You can set ROOTDIR to root system dir
 #ROOTDIR=
 
-PROGVERSION="20230328"
+PROGVERSION="20230406"
 
 # TODO: check /etc/system-release
 
@@ -884,7 +884,7 @@ case "$1" in
 		echo " -c                     - print number of CPU cores"
 		echo " -i                     - print virtualization type"
 		echo " -m                     - print system memory size (in MB)"
-		echo " -y                     - print running service manager"
+		echo " -y|--service-manager   - print running service manager"
 		echo " -z                     - print current CPU MHz"
 		echo " --glibc-version        - print system glibc version"
 		echo
@@ -993,7 +993,8 @@ case "$1" in
 		pkgvendor
 		exit 0
 		;;
-	-y)
+	-y|--service-manager)
+		override_distrib "$2"
 		get_service_manager
 		;;
 	-V)