whisper : add C++17 standard

This commit adds the C++17 standard to the CMakeLists.txt file.

The motivatiion for this is that ggml sets this and it would seem
alright to have the same standard in whisper too.

Author: danbev

CMakeLists.txt

@@ -5,6 +5,9 @@ include(CheckIncludeFileCXX)
 
 set(SOVERSION 1)
 
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
 #set(CMAKE_WARN_DEPRECATED YES)
 set(CMAKE_WARN_UNUSED_CLI YES)