Don't provide default value for quantile=

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@60345 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.neighbors/main.c

@@ -209,7 +209,6 @@ int main(int argc, char *argv[])
     parm.quantile->multiple = YES;
     parm.quantile->description = _("Quantile to calculate for method=quantile");
     parm.quantile->options = "0.0-1.0";
-    parm.quantile->answer = "0.5";
 
     flag.align = G_define_flag();
     flag.align->key = 'a';