gpu: ipu-v3: Fix U/V offset macros for planar 4:2:0

The U and V offset macros for planar 4:2:0 (U_OFFSET, V_OFFSET, and
UV_OFFSET), are not correct. The height component to the offset was
calculated as:

(pix->width * y / 4)

But this does not produce correct offsets for odd values of y (luma
line #). The luma line # must be decimated by two to produce the
correct U/V line #, so the correct formula is:

(pix->width * (y / 2) / 2)

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/ipu-v3/ipu-cpmem.c

@@ -530,17 +530,17 @@ static const struct ipu_rgb def_bgra_16 = {
 
 #define Y_OFFSET(pix, x, y)	((x) + pix->width * (y))
 #define U_OFFSET(pix, x, y)	((pix->width * pix->height) +		\
-				 (pix->width * (y) / 4) + (x) / 2)
+				 (pix->width * ((y) / 2) / 2) + (x) / 2)
 #define V_OFFSET(pix, x, y)	((pix->width * pix->height) +		\
 				 (pix->width * pix->height / 4) +	\
-				 (pix->width * (y) / 4) + (x) / 2)
+				 (pix->width * ((y) / 2) / 2) + (x) / 2)
 #define U2_OFFSET(pix, x, y)	((pix->width * pix->height) +		\
 				 (pix->width * (y) / 2) + (x) / 2)
 #define V2_OFFSET(pix, x, y)	((pix->width * pix->height) +		\
 				 (pix->width * pix->height / 2) +	\
 				 (pix->width * (y) / 2) + (x) / 2)
 #define UV_OFFSET(pix, x, y)	((pix->width * pix->height) +	\
-				 (pix->width * (y) / 2) + (x))
+				 (pix->width * ((y) / 2)) + (x))
 #define UV2_OFFSET(pix, x, y)	((pix->width * pix->height) +	\
 				 (pix->width * y) + (x))