cmake: fix else statement

build/CMakeLists.txt

@@ -188,13 +188,13 @@ endif ()
 include(CheckCXXCompilerFlag)
 CHECK_CXX_COMPILER_FLAG("-std=c++17" CXX17_SUPPORTED)
 CHECK_CXX_COMPILER_FLAG("-std=c++11" CXX11_SUPPORTED)
-if (CXX17_SUPPORTED)
-  set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17" )
-elseif (CXX11_SUPPORTED)
-  set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11" )
-else
+if(CXX17_SUPPORTED)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17")
+elseif(CXX11_SUPPORTED)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+else()
   message(SEND_ERROR "C++17 nor C++11 standard not seems to be supported by compiler. Too old version?")
-endif ()
+endif()
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
   set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pipe")