Zero memory of format struct to prevent sigsegv.

git-svn-id: svn://svn.code.sf.net/p/rdesktop/code/rdesktop/trunk@1730 423420c4-83ab-492f-b58f-81f9feb106b5

rdpsnd_libao.c

@@ -111,6 +111,7 @@ libao_set_format(RD_WAVEFORMATEX * pwfx)
 {
 	ao_sample_format format;
 
+	memset(&format, 0, sizeof(format));
 	format.bits = pwfx->wBitsPerSample;
 	format.channels = pwfx->nChannels;
 	format.rate = 44100;