radv: add missing meson c++ visibility arguments

Fixes: 6f3aee40f9 "radv: using tls to store llvm related info
                             and speed up compiles (v10)"
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

src/amd/vulkan/meson.build

@@ -144,6 +144,7 @@ libvulkan_radeon = shared_library(
     idep_nir,
   ],
   c_args : [c_vis_args, no_override_init_args, radv_flags],
+  cpp_args : [cpp_vis_args, radv_flags],
   link_args : [ld_args_bsymbolic, ld_args_gc_sections],
   install : true,
 )