Examples: Vulkan: Add c++ version to CMakeLists (#5459)

Co-authored-by: Shriram <“shriram.r@technovert.com”>
diff --git a/examples/example_glfw_vulkan/CMakeLists.txt b/examples/example_glfw_vulkan/CMakeLists.txt
index 55a8040..a6e5bf9 100644
--- a/examples/example_glfw_vulkan/CMakeLists.txt
+++ b/examples/example_glfw_vulkan/CMakeLists.txt
@@ -10,6 +10,7 @@
   set(CMAKE_BUILD_TYPE Debug CACHE STRING "" FORCE)
 endif()
 
+set(CMAKE_CXX_STANDARD 11)
 set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DVK_PROTOTYPES")
 set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DVK_PROTOTYPES")