configure.ac / meson: depend on libnativewindow when appropriate

libnativewindow is only available on O or greater, and it's
required for some features.

Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
diff --git a/meson.build b/meson.build
index 7b33775..715c966 100644
--- a/meson.build
+++ b/meson.build
@@ -726,6 +726,9 @@
     dependency('hardware'),
     dependency('sync'),
   ]
+  if get_option('platform-sdk-version') >= 26
+    dep_android += dependency('nativewindow')
+  endif
   pre_args += '-DHAVE_ANDROID_PLATFORM'
 endif
 if with_platform_haiku