message: cmake: avoid duplication of -Winit-self flag
diff: @@ -120,7 +120,6 @@ if(CV_GCC OR CV_CLANG)
  add_extra_compiler_option(-Wshadow)
  add_extra_compiler_option(-Wsign-promo)
  add_extra_compiler_option(-Wuninitialized)
  - add_extra_compiler_option(-Winit-self)
  if(CV_GCC AND (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 6.0) AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0))
  add_extra_compiler_option(-Wno-psabi)
  endif()
  