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

diff -u -r mesa-19.2.2.orig/include/meson.build mesa-19.2.2/include/meson.build
--- mesa-19.2.2.orig/include/meson.build	2019-10-25 21:55:51.441084000 +0200
+++ mesa-19.2.2/include/meson.build	2019-10-25 21:58:07.781272000 +0200
@@ -22,7 +22,6 @@
 inc_d3d9 = include_directories('D3D9')
 inc_haikugl = include_directories('HaikuGL')
 
-if not glvnd_has_headers_and_pc_files
   if with_gles1 or with_gles2 or with_opengl or with_egl
     install_headers('KHR/khrplatform.h', subdir : 'KHR')
   endif
@@ -78,7 +77,6 @@
       subdir : 'EGL',
     )
   endif
-endif
 
 # Non-upstream headers
 if with_egl