bug #14418: Remove addition of "-Wno-deprecated" compiler flag

The suppression seems no longer necessary, at least
in all the configs I've tried, which includes old PPC OS X 10.5
and Intel OS X 10.8, with gcc and clang.

Change-Id: Ief54e3cfb0abc6959460ed477638cee7420492cf
Merge topic 'remove-Wno-deprecated' into master

9fd96021 bug #14418: Remove addition of "-Wno-deprecated" compiler flag