Input: wacom - remove code duplication

Replaces code to calculate Intuos5 physical dimensions with a call
to an existing function that performs the same task.

Signed-off-by: Jason Gerecke <[e-mail]>
Reviewed-by: Chris Bagwell <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/tablet/wacom_sys.c

···
 			features->device_type = BTN_TOOL_FINGER;
 			features->pktlen = WACOM_PKGLEN_BBTOUCH3;
 
-			features->x_phy =
-				(features->x_max * 100) / features->x_resolution;
-			features->y_phy =
-				(features->y_max * 100) / features->y_resolution;
+			wacom_set_phy_from_res(features);
 
 			features->x_max = 4096;
 			features->y_max = 4096;