IntelLLVM: Replace -Qstd= with -Qstd: on Windows

The latter is the documented form [1].

[1] https://www.intel.com/content/www/us/en/develop/documentation/oneapi-dpcpp-cpp-compiler-dev-guide-and-reference/top/compiler-reference/compiler-options/language-options/std-qstd.html

Modules/Compiler/IntelLLVM-CXX.cmake

@@ -53,14 +53,14 @@ else()
   set(CMAKE_CXX11_STANDARD_COMPILE_OPTION  "")
   set(CMAKE_CXX11_EXTENSION_COMPILE_OPTION "")
 
-  set(CMAKE_CXX14_STANDARD_COMPILE_OPTION  "-Qstd=c++14")
-  set(CMAKE_CXX14_EXTENSION_COMPILE_OPTION "-Qstd=c++14")
+  set(CMAKE_CXX14_STANDARD_COMPILE_OPTION  "-Qstd:c++14")
+  set(CMAKE_CXX14_EXTENSION_COMPILE_OPTION "-Qstd:c++14")
 
-  set(CMAKE_CXX17_STANDARD_COMPILE_OPTION  "-Qstd=c++17")
-  set(CMAKE_CXX17_EXTENSION_COMPILE_OPTION "-Qstd=c++17")
+  set(CMAKE_CXX17_STANDARD_COMPILE_OPTION  "-Qstd:c++17")
+  set(CMAKE_CXX17_EXTENSION_COMPILE_OPTION "-Qstd:c++17")
 
-  set(CMAKE_CXX20_STANDARD_COMPILE_OPTION  "-Qstd=c++20")
-  set(CMAKE_CXX20_EXTENSION_COMPILE_OPTION "-Qstd=c++20")
+  set(CMAKE_CXX20_STANDARD_COMPILE_OPTION  "-Qstd:c++20")
+  set(CMAKE_CXX20_EXTENSION_COMPILE_OPTION "-Qstd:c++20")
 endif()
 
 __compiler_check_default_language_standard(CXX 2020 14)