9a6cdce3 was trying to fix the problem
with exposing deprecated vars and functions in system's error_code.hpp
include file by patching bundled boost version.  This approach would
only make sense, when upstream version is going to be fixed ASAP. Apply
another approach, and follow the same pattern as applied in external
libraries, by defining

  -DBOOST_ERROR_CODE_HEADER_ONLY \
  -DBOOST_SYSTEM_NO_DEPRECATED

instead of patching bundled boost version.  This way, the code would
work with unpatched system boost 1.59 final as well.

Change-Id: I8684ca458ea4a5b7d7c3c3acfe7c14a6d19bc665
Reviewed-on: https://gerrit.libreoffice.org/18201Reviewed-by: David Ostrovsky <david@ostrovsky.org>
Tested-by: David Ostrovsky <david@ostrovsky.org>