[lldb] Don't try to set -Wno-deprecated-declarations

[teemperor]

Summary

By suppressing all deprecation warnings we are not getting any heads up if external libraries
(e.g. Python) are deprecating parts of their API and we only find out when they actually
remove these functions.

This was originally done to suppress LLDB's use of auto_ptr which we stopped using some
time ago.

[teemperor]

There is some cleanup that needs to be done before this can land. https://reviews.llvm.org/D104374 fixes some deprecation warnings from Python and there are some macOS APIs that got deprecated (which I still need to fix)

[kastiglione]

thanks!

lldb/cmake/modules/LLDBConfig.cmake

 if (LLVM_EXTERNAL_CLANG_SOURCE_DIR)
   include_directories(${LLVM_EXTERNAL_CLANG_SOURCE_DIR}/include)
 else ()
   include_directories(${CMAKE_SOURCE_DIR}/tools/clang/include)
 endif ()
 include_directories("${CMAKE_CURRENT_BINARY_DIR}/../clang/include")
 
 # Disable GCC warnings
-check_cxx_compiler_flag("-Wno-deprecated-declarations" CXX_SUPPORTS_NO_DEPRECATED_DECLARATIONS)
-append_if(CXX_SUPPORTS_NO_DEPRECATED_DECLARATIONS "-Wno-deprecated-declarations" CMAKE_CXX_FLAGS)
-
 check_cxx_compiler_flag("-Wno-unknown-pragmas" CXX_SUPPORTS_NO_UNKNOWN_PRAGMAS)
 append_if(CXX_SUPPORTS_NO_UNKNOWN_PRAGMAS "-Wno-unknown-pragmas" CMAKE_CXX_FLAGS)
 
 check_cxx_compiler_flag("-Wno-strict-aliasing" CXX_SUPPORTS_NO_STRICT_ALIASING)
 append_if(CXX_SUPPORTS_NO_STRICT_ALIASING "-Wno-strict-aliasing" CMAKE_CXX_FLAGS)
 
 # Disable Clang warnings
 check_cxx_compiler_flag("-Wno-vla-extension" CXX_SUPPORTS_NO_VLA_EXTENSION)