File n_add-Mesa-headers-again.patch of Package Mesa

diff -dupr mesa-20.0.0.orig/include/meson.build mesa-20.0.0/include/meson.build
--- mesa-20.0.0.orig/include/meson.build	2020-02-21 14:11:14.623397341 +0100
+++ mesa-20.0.0/include/meson.build	2020-02-21 14:13:05.620425210 +0100
@@ -22,10 +22,8 @@ inc_include = include_directories('.')
 inc_d3d9 = include_directories('D3D9')
 inc_haikugl = include_directories('HaikuGL')
 
-if not with_glvnd
   if with_gles1 or with_gles2 or with_opengl or with_egl
     install_headers('KHR/khrplatform.h', subdir : 'KHR')
-  endif
 
   if with_gles1
     install_headers(