comms/gnuradio: Fix build after 833bce4

Commit 833bce4 indirectly broke comms/gnuradio, making the linker
not find its libraries anymore:

  ld: error: unable to find library -lgsl
  ld: error: unable to find library -lgslcblas

Fix build by adding ${LOCALBASE}/lib to LDFLAGS.

Author: martymac

comms/gnuradio/Makefile

@@ -74,6 +74,7 @@ USE_WX=		3.2
 USE_QT=		buildtools core gui xml qmake widgets
 WX_COMPS=	wx python:run
 USE_LDCONFIG=	yes
+LDFLAGS+=	-L${LOCALBASE}/lib
 LIBSTRIP_FILES=	analog audio blocks channels digital dtv fec fft\
 		filter pmt qtgui runtime trellis video-sdl\
 		vocoder wavelet