doc: Update config file storage paths descriptions

[doc] Update config file storage paths descriptions. JB#61888

Change the description to detail the default build time set values for
both StorageRoot and UserStorage paths. Change the default UserStorage
to be ".config" in Makefile.am. The paths are read from configuration
files on both connman and connman-vpn.

connman/Makefile.am

@@ -228,8 +228,9 @@ scriptdir = $(libdir)/connman/scripts
 
 storageroot = $(localstatedir)/lib
 
-# Path in users' home dir to use as storage dir
-userstorage = ".local/share/system/privileged"
+# Path in users' home dir to use as a storage dir. connman/connman-vpn will
+# be created when omitted.
+userstorage = ".config"
 
 configdir = ${sysconfdir}/connman
 

connman/doc/config-format.txt

@@ -3,11 +3,17 @@ Connman configuration file format
 
 Connman uses configuration files to provision existing services. Connman will
 be looking for its configuration files at STORAGEDIR which by default points
-to /var/lib/connman/. Configuration file names must not include other
-characters than letters or numbers and must have a .config suffix.
-Those configuration files are text files with a simple key-value pair format,
-organized into sections. Values do not comprise leading or trailing whitespace.
-We typically have one file per provisioned network.
+to /var/lib/connman/. This can be overridden with a value "StorageRoot" in the
+main configuration file, typically in /etc/connman/main.conf. With multiuser
+support enabled, the user-specific configuration data is stored by default into
+users' home at $HOME/.config and can be overridden with a value "UserStorage"
+in the configuration file.
+
+Configuration file names must not include other characters than letters or
+numbers and must have a .config suffix. Those configuration files are text
+files with a simple key-value pair format, organized into sections. Values do
+not comprise leading or trailing whitespace. We typically have one file per
+provisioned network.
 
 If the config file is removed, then Connman tries to remove the
 provisioned services. If an individual service inside a config is removed,

connman/doc/vpn-config-format.txt

@@ -3,11 +3,18 @@ Connman configuration file format for VPN
 
 Connman VPN uses configuration files to provision existing providers.
 vpnd will be looking for its configuration files at VPN_STORAGEDIR
-which by default points to /var/lib/connman-vpn. Configuration file names
-must not include other characters than letters or numbers and must have
-a .config suffix. Those configuration files are text files with a simple
-key-value pair format organized into sections. Values do not comprise leading
-trailing whitespace. We typically have one file per provisioned network.
+which by default points to /var/lib/connman-vpn. This can be overridden with a
+value "StorageRoot" in the connman-vpn configuration file, typically in
+/etc/connman/connman-vpn.conf. With multiuser support enabled, the
+user-specific configuration data is stored by default into users' home at
+$HOME/.config and can be overridden with a value "UserStorage" in the
+configuration file.
+
+Configuration file names must not include other characters than letters or
+numbers and must have a .config suffix. Those configuration files are text
+files with a simple key-value pair format organized into sections. Values do
+not comprise leading or trailing whitespace. We typically have one file per
+provisioned network.
 
 If the config file is removed, then vpnd tries to remove the
 provisioned service. If an individual service entry inside a config is removed,