Pullup ticket #4440 - requested by asau
devel/boost-libs: build fix

Revisions pulled up:
- devel/boost-libs/Makefile                                     1.28

---
   Module Name:	pkgsrc
   Committed By:	asau
   Date:		Tue Jul  1 22:16:43 UTC 2014

   Modified Files:
   	pkgsrc/devel/boost-libs: Makefile

   Log Message:
   Work around PR toolchain/48878: make it build on NetBSD/i386 with GCC 4.8.
Pullup ticket #4440.
Don't use __cxa_atexit on older platforms.
multimedia/ffmpeg010: backport asm fix from trunk.
Merge branch 'pkgsrc_2014Q2' into joyent/feature/miscfix/2014Q2