meson: rename options as per meson's style guide

see https://mesonbuild.com/Style-guide.html

meson.build

@@ -153,7 +153,7 @@ dbus_dep = dependency('dbus-1')
 #optional dependencies
 jack_dep = dependency('jack', version : '>= 1.9.10', required : false)
 
-if get_option('enable_gstreamer')
+if get_option('gstreamer')
   glib_dep = dependency('glib-2.0', version : '>=2.32.0')
   gobject_dep = dependency('gobject-2.0')
   gmodule_dep = dependency('gmodule-2.0')
@@ -169,7 +169,7 @@ subdir('spa')
 subdir('src')
 subdir('pkgconfig')
 
-if get_option('enable_docs')
+if get_option('docs')
   doxygen = find_program('doxygen', required : false)
   if doxygen.found()
     subdir('doc')
@@ -178,7 +178,7 @@ if get_option('enable_docs')
   endif
 endif
 
-if get_option('enable_man')
+if get_option('man')
   xmltoman = find_program('xmltoman', required : false)
   if xmltoman.found()
     subdir('man')

meson_options.txt

@@ -1,12 +1,12 @@
-option('enable_docs',
+option('docs',
        description: 'Build documentation',
        type: 'boolean',
        value: false)
-option('enable_man',
+option('man',
        description: 'Build manpages',
        type: 'boolean',
        value: false)
-option('enable_gstreamer',
+option('gstreamer',
        description: 'Build GStreamer plugins',
        type: 'boolean',
        value: false)

src/meson.build

@@ -6,6 +6,6 @@ subdir('tools')
 subdir('modules')
 subdir('examples')
 
-if get_option('enable_gstreamer')
+if get_option('gstreamer')
   subdir('gst')
 endif