Remove OpenBSD SLIBNAME magic, it seems unnecessary and breaks compilation.

Originally committed as revision 16087 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -1405,9 +1405,6 @@ case $target_os in
         disable need_memalign
         LIBOBJFLAGS='$(PIC)'
         SHFLAGS='-shared'
-        SLIBNAME='$(SLIBPREF)$(FULLNAME)$(SLIBSUF).$(LIBVERSION)'
-        SLIBNAME_WITH_VERSION='$(SLIBNAME)'
-        SLIBNAME_WITH_MAJOR='$(SLIBNAME)'
         oss_demuxer_extralibs="-lossaudio"
         oss_muxer_extralibs="-lossaudio"
         ;;