meson: build raw1394 plugin

https://bugzilla.gnome.org/show_bug.cgi?id=784134

ext/meson.build

@@ -10,7 +10,7 @@ if cc.get_id() != 'msvc'
   subdir('dv')
 endif
 subdir('libpng')
-# subdir('raw1394')
+subdir('raw1394')
 subdir('pulse')
 subdir('shout2')
 subdir('soup')

ext/raw1394/meson.build

+raw1394_dep = dependency('libraw1394', version: '>= 2.0.0', required: false)
+avc1394_dep = dependency('libavc1394', version: '>= 0.5.4', required: false)
+iec61883_dep = dependency('libiec61883', version: '>= 1.0.0', required: false)
+
+have_1394 = false
+if raw1394_dep.found() and iec61883_dep.found() and avc1394_dep.found()
+  if cc.has_function('avc1394_send_command', dependencies: avc1394_dep)
+    if cc.has_function('rom1394_free_directory', dependencies: avc1394_dep)
+      have_1394 = true
+    endif
+  endif
+endif
+
+if have_1394
+  library('gst1394',
+    'gst1394.c', 'gst1394probe.c', 'gstdv1394src.c', 'gsthdv1394src.c', 'gst1394clock.c',
+    c_args : gst_plugins_good_args + ['-DHAVE_LIBIEC61883'],
+    include_directories : [configinc, libsinc],
+    dependencies : [gstvideo_dep, gstbase_dep, raw1394_dep, avc1394_dep, iec61883_dep],
+    install : true,
+    install_dir : plugins_install_dir)
+endif