profile: remove DiveCartesianAxis::gridColor member variable

This was only used in the constructor to create the pen for
the grid lines. Not need to keep it around.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

profile-widget/divecartesianaxis.cpp

@@ -24,7 +24,6 @@ DiveCartesianAxis::DiveCartesianAxis(Position position, int integralDigits, int
 	printMode(printMode),
 	position(position),
 	fractionalDigits(fractionalDigits),
-	gridColor(gridColor),
 	scene(scene),
 	orientation(LeftToRight),
 	min(0),

profile-widget/divecartesianaxis.h

@@ -57,7 +57,6 @@ private:
 	int fractionalDigits;
 	QRectF rect; // Rectangle to fill with grid lines
 	QPen gridPen;
-	color_index_t gridColor;
 	ProfileScene &scene;
 	QString textForValue(double value) const;
 	virtual QColor colorForValue(double value) const;