libvulkan: get android_get_exported_namespace from real header

Bug: 134185757
Test: build, flash and boot.
Change-Id: Ife2cab93ebddf898ed8c031a33e7997ae8d5d63f
diff --git a/vulkan/libvulkan/Android.bp b/vulkan/libvulkan/Android.bp
index 993b751..85ef475 100644
--- a/vulkan/libvulkan/Android.bp
+++ b/vulkan/libvulkan/Android.bp
@@ -75,6 +75,7 @@
 
     header_libs: [
         "hwvulkan_headers",
+        "libnativeloader-dummy-headers",
         "vulkan_headers",
     ],
     export_header_lib_headers: ["vulkan_headers"],