sox_ng: Remove (lib)speex un-expected inclusion by discovery

Building sox_ng under certain environments inadvertantly tries to include Speex code.
This patch forces sox_ng to build without Speex codec references.

Signed-off-by: Ted Hess <[email protected]>

Author: thess

sound/sox_ng/Makefile

@@ -46,6 +46,7 @@ CONFIGURE_ARGS += \
 		--without-libltdl \
 		--with-flac \
 		--without-ladspa \
+		--without-speexdsp \
 		--without-png \
 		--without-sndfile \
 		--with-opus \