vulkan: fix build dependency issue with generated files

On machines with many cores, you can run into that issue :

../mesa-9999/src/vulkan/overlay-layer/overlay.cpp:42:10: fatal error: vk_enum_to_str.h: No such file or directory

v2: Move declare_dependency around (Eric)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reported-by: Jan Ziak
Cc: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>

src/vulkan/util/meson.build

@@ -44,3 +44,15 @@ libvulkan_util = static_library(
   c_args : [c_vis_args, vulkan_wsi_args],
   build_by_default : false,
 )
+
+idep_vulkan_util_headers = declare_dependency(
+  sources : vk_enum_to_str[1],
+  include_directories : include_directories('.')
+)
+
+idep_vulkan_util = declare_dependency(
+  sources : vk_enum_to_str[1],
+  link_with : libvulkan_util,
+  include_directories : include_directories('.'),
+  dependencies : idep_vulkan_util_headers
+)