Fix LIBDIR for non-prefix users

git-svn-id: https://lmms.svn.sf.net/svnroot/lmms/trunk/lmms@1208 0778d3d1-df1d-0410-868b-ea421aaaa00d

configure.in

@@ -18,10 +18,14 @@ AM_PROG_LIBTOOL
 
 if ! test -z "${prefix}" -o "${prefix}" = "NONE" ; then
 	CFLAGS="$CFLAGS -I${prefix}/include"
-	CPPFLAGS="$CPPFLAGS -I${prefix}/include -DLIBDIR='\"${libdir}\"'"
+	CPPFLAGS="$CPPFLAGS -I${prefix}/include"
 	LDFLAGS="$LDFLAGS -L${prefix}/bin"
 fi
 
+if ! test -z "${libdir}" ; then
+	CPPFLAGS="$CPPFLAGS -DLIBDIR='\"${libdir}\"'"
+fi
+
 AH_TEMPLATE(BUILD_LINUX, [Build LMMS for Linux])
 AH_TEMPLATE(BUILD_WIN32, [Build LMMS for Win32])
 AH_TEMPLATE(WIN32, [Build LMMS for Win32])