HPCC-15761 Suppress spurious warnings on OSX builds

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>

cmake_modules/commonSetup.cmake

@@ -402,6 +402,7 @@ IF ("${COMMONSETUP_DONE}" STREQUAL "")
       SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror=logical-op-parentheses -Werror=bool-conversions -Werror=return-type -Werror=comment")
       if (APPLE)
         SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
+        SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-deprecated-declarations")
       endif ()
       SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}  -Werror=bitwise-op-parentheses -Werror=tautological-compare")
       SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}  -Wno-switch-enum -Wno-format-zero-length -Wno-switch")