Use proper path seperator for LADSPA_PATH

According to http://www.ladspa.org/ladspa_sdk/shared_plugins.html,
LADSPA_PATH is supposed to be delimited by colons.  This patch does so,
except on Windows.  On Windows we use ';' instead of ':' since colon is
a legal character for a path.

include/lmms_basics.h

@@ -128,6 +128,13 @@ const ch_cnt_t SURROUND_CHANNELS =
 #endif
 
 
+#ifdef LMMS_BUILD_WIN32
+#define PATH_SEPERATOR = ';';
+#else
+#define PATH_SEPERATOR = ':';
+#endif
+
+
 
 typedef sample_t sampleFrame[DEFAULT_CHANNELS];
 typedef sample_t surroundSampleFrame[SURROUND_CHANNELS];