add an option to enable/disable libliftoff

instead of always using it if found

backend/drm/meson.build

@@ -16,7 +16,7 @@ libliftoff = dependency(
 	'libliftoff',
 	version: '>=0.4.0',
 	fallback: 'libliftoff',
-	required: false,
+	required: get_option('libliftoff'),
 )
 
 if not (hwdata.found() and libdisplay_info.found() and features['session'])

meson.build

@@ -99,6 +99,7 @@ features = {
 internal_features = {
 	'xcb-errors': false,
 	'egl': false,
+	'libliftoff': false,
 }
 internal_config = configuration_data()
 

meson_options.txt

@@ -8,3 +8,4 @@ option('allocators', type: 'array', choices: ['auto', 'gbm'], value: ['auto'],
 	description: 'Select built-in allocators')
 option('session', type: 'feature', value: 'auto', description: 'Enable session support')
 option('color-management', type: 'feature', value: 'auto', description: 'Enable support for color management')
+option('libliftoff', type: 'feature', value: 'auto', description: 'Enable support for libliftoff')