meson: produce summary() when 0.53.0 is present

Use the summary() feature, similar to the autotools build.

This was introduced with 0.53.0 so guard on that version. We don't want
to bump the required version, even though 0.53.0 is available on Debian
old-stable (buster-backports), Ubuntu 20.04 (focal) and newer distros.

v2: Don't bump the required version

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>

Author: evelikov-work

meson.build

@@ -17,6 +17,8 @@ libva_dep = dependency('libva', version: '>= 1.1.0')
 libva_utils_flags = [ '-Wno-unused-parameter',
                       '-Wno-sign-compare' ]
 
+backends = ''
+
 # DRM
 use_drm = false
 if get_option('drm') != 'false'
@@ -32,6 +34,7 @@ if get_option('drm') != 'false'
     endif
   endforeach
   if use_drm
+    backends += ' drm'
     libva_utils_flags += [ '-DHAVE_VA_DRM=1' ]
   endif
 endif
@@ -51,6 +54,7 @@ if get_option('x11') != 'false'
     endif
   endforeach
   if use_x11
+    backends += ' x11'
     libva_utils_flags += [ '-DHAVE_VA_X11=1' ]
   endif
 endif
@@ -70,6 +74,7 @@ if get_option('wayland') != 'false'
     endif
   endforeach
   if use_wayland
+    backends += ' wayland'
     libva_utils_flags += [ '-DHAVE_VA_WAYLAND=1' ]
   endif
 endif
@@ -89,3 +94,12 @@ subdir('vendor/intel/sfcsample')
 if get_option('tests')
   subdir('test')
 endif
+
+if meson.version().version_compare('>= 0.53')
+  summary({
+    'Libva VA-API version' : libva_dep.version(),
+    'Installation prefix' : get_option('prefix'),
+    'Extra window systems' : backends,
+    'Enable Unit-tests': get_option('tests')
+  }, bool_yn: true)
+endif