[patch] fix compilation with boost 1.67

Hi everyone @ gr-osmosdr, I have created a small pull request to fix compilation with boost-1.67. I filed it on your github mirror, but am not sure that's the way to make a contribution. It's available here: https://github.com/osmocom/gr-osmosdr/pull/13 I'll also include the patch here for completeness: diff -ura gr-osmosdr.orig/lib/CMakeLists.txt gr-osmosdr/lib/CMakeLists.txt --- gr-osmosdr.orig/lib/CMakeLists.txt 2018-06-10 12:06:35.662484236 +0200 +++ gr-osmosdr/lib/CMakeLists.txt 2018-06-10 12:06:51.886207437 +0200 @@ -43,6 +43,8 @@ time_spec.cc ) +list(APPEND Boost_LIBRARIES pthread) + GR_OSMOSDR_APPEND_LIBS( ${Boost_LIBRARIES} ${GNURADIO_ALL_LIBRARIES} Cheers, Maxime