Meson fixes for native contexts

• Fix MSM nctx not building by x64 CI host
• Make MSM compiler requirements common to all DRM renderers

@robclark

meson.build

@@ -283,11 +283,7 @@ have_vla = not cc.has_header_symbol('stdlib.h', '__STDC_NO_VLA__')
 
 drm_renderers = get_option('drm-renderers')
 
-# DRM renderers require support for VLAs and packed and aligned structs
-with_drm_msm = (have_struct_attribute_packed
-            and have_struct_attribute_aligned
-            and have_vla
-            and ['aarch64'].contains(host_machine.cpu_family())
+with_drm_msm = (not ['arm'].contains(target_machine.cpu_family())
             and (get_option('drm-msm-experimental') or drm_renderers.contains('msm')))
 if with_drm_msm
   conf_data.set('ENABLE_DRM_MSM', 1)
@@ -301,6 +297,14 @@ endif
 
 with_drm = with_drm_msm or with_drm_amdgpu
 
+if with_drm
+   if (not have_struct_attribute_packed or
+       not have_struct_attribute_aligned or
+       not have_vla)
+      error('DRM renderers require compiler support for VLAs, packed and aligned structs')
+   endif
+endif
+
 with_check_gl_errors = get_option('check-gl-errors')
 if with_check_gl_errors
    conf_data.set('CHECK_GL_ERRORS', 1)