build: Port to meson

meson is a build system focused on speed an ease of use, which
helps speeding up the software development. This patch adds meson
support along autotools.

introspection/meson.build

@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2021 Iñigo Martinez <inigomartinez@gmail.com>
+
+# DBus Introspection files
+mm_ifaces_all = files('all.xml')
+mm_ifaces_test = files('tests/org.freedesktop.ModemManager1.Test.xml')
+
+mm_ifaces = files('org.freedesktop.ModemManager1.xml')
+
+mm_ifaces_bearer = files('org.freedesktop.ModemManager1.Bearer.xml')
+mm_ifaces_call = files('org.freedesktop.ModemManager1.Call.xml')
+
+mm_ifaces_modem = files(
+  'org.freedesktop.ModemManager1.Modem.Firmware.xml',
+  'org.freedesktop.ModemManager1.Modem.Location.xml',
+  'org.freedesktop.ModemManager1.Modem.Messaging.xml',
+  'org.freedesktop.ModemManager1.Modem.Modem3gpp.ProfileManager.xml',
+  'org.freedesktop.ModemManager1.Modem.Modem3gpp.Ussd.xml',
+  'org.freedesktop.ModemManager1.Modem.Modem3gpp.xml',
+  'org.freedesktop.ModemManager1.Modem.ModemCdma.xml',
+  'org.freedesktop.ModemManager1.Modem.Oma.xml',
+  'org.freedesktop.ModemManager1.Modem.Signal.xml',
+  'org.freedesktop.ModemManager1.Modem.Simple.xml',
+  'org.freedesktop.ModemManager1.Modem.Time.xml',
+  'org.freedesktop.ModemManager1.Modem.Voice.xml',
+  'org.freedesktop.ModemManager1.Modem.xml',
+)
+
+mm_ifaces_sim = files('org.freedesktop.ModemManager1.Sim.xml')
+mm_ifaces_sms = files('org.freedesktop.ModemManager1.Sms.xml',)
+
+install_data(
+  mm_ifaces + mm_ifaces_bearer + mm_ifaces_call + mm_ifaces_modem + mm_ifaces_sim + mm_ifaces_sms,
+  install_dir: dbus_interfaces_dir,
+)