Fix crash issue when enable lissajous figure in certain case

DSView/pv/dialogs/lissajousoptions.cpp

@@ -57,7 +57,7 @@ LissajousOptions::LissajousOptions(SigSession &session, QWidget *parent) :
     _percent->setRange(100, 100);
     _percent->setEnabled(false);
     if (_session.cur_samplelimits() > WellLen) {
-        int min = WellLen*100.0/_session.cur_samplelimits();
+        int min = ceil(WellLen*100.0/_session.cur_samplelimits());
         _percent->setEnabled(true);
         _percent->setRange(min, 100);
         _percent->setValue(min);