Input: wacom - fix physical size calculation for 3rd-gen Bamboo

This calculation determines the physical dimensions of the tablet,
used later on in calculate_touch_res to obtain the touch sensor
resolution.

Instead of dividing the logical size by the resolution, the current
code performs a multiplication. This doesn't pose a problem for the
3rd-gen Bamboo since the resolution and scale factor happen to be
identical, but will produce an incorrect result for other cases.

Signed-off-by: Jason Gerecke <killertofu@gmail.com>
Reviewed-by: Chris Bagwell <chris@cnpbagwell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/tablet/wacom_sys.c

@@ -184,9 +184,9 @@ static int wacom_parse_logical_collection(unsigned char *report,
 		 * data before its overwritten.
 		 */
 		features->x_phy =
-			(features->x_max * features->x_resolution) / 100;
+			(features->x_max * 100) / features->x_resolution;
 		features->y_phy =
-			(features->y_max * features->y_resolution) / 100;
+			(features->y_max * 100) / features->y_resolution;
 
 		features->x_max = features->y_max =
 			get_unaligned_le16(&report[10]);