cmake: Optimize Android VVL download logic

Improve the Vulkan Validation Layer (VVL) download logic for Android by checking
for the final library file instead of just the zip archive. This prevents
unnecessary re-downloads and extractions when the library is already in place.

The check now looks for libVkLayer_khronos_validation.so in the final
destination path before attempting to download and extract the archive.

CMakeLists.txt

@@ -91,20 +91,25 @@ option(ENABLE_OPENSSL "Enable OpenSSL backend for ISslConnection" ${DEFAULT_ENAB
 if (ANDROID AND YUZU_DOWNLOAD_ANDROID_VVL)
     set(vvl_version "sdk-1.3.261.1")
     set(vvl_zip_file "${CMAKE_BINARY_DIR}/externals/vvl-android.zip")
-    if (NOT EXISTS "${vvl_zip_file}")
+
+    set(vvl_lib_path "${CMAKE_CURRENT_SOURCE_DIR}/src/android/app/src/main/jniLibs/arm64-v8a/")
+    set(vvl_final_lib "${vvl_lib_path}/libVkLayer_khronos_validation.so")
+
+    if (NOT EXISTS "${vvl_final_lib}")
         # Download and extract validation layer release to externals directory
+        if (NOT EXISTS "${vvl_zip_file}")
             set(vvl_base_url "https://github.com/KhronosGroup/Vulkan-ValidationLayers/releases/download")
-        file(DOWNLOAD "${vvl_base_url}/${vvl_version}/android-binaries-${vvl_version}-android.zip"
+            file(DOWNLOAD "${vvl_base_url}/vulkan-sdk-${vvl_version}/android-binaries-${vvl_version}.zip"
                 "${vvl_zip_file}" SHOW_PROGRESS)
             execute_process(COMMAND ${CMAKE_COMMAND} -E tar xf "${vvl_zip_file}"
                             WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/externals")
         endif()
 
         # Copy the arm64 binary to src/android/app/main/jniLibs
-    set(vvl_lib_path "${CMAKE_CURRENT_SOURCE_DIR}/src/android/app/src/main/jniLibs/arm64-v8a/")
         file(COPY "${CMAKE_BINARY_DIR}/externals/android-binaries-${vvl_version}/arm64-v8a/libVkLayer_khronos_validation.so"
                 DESTINATION "${vvl_lib_path}")
     endif()
+endif()
 
 if (ANDROID)
     set(CMAKE_SKIP_INSTALL_RULES ON)