video: ipu_disp: squash clang warning

Since rgb2ycbcr_coeff and friends are declared const, but assigned
to a void pointer, clang will warn that the const is implicity casted
away. If the pointer is changed to void const * gcc will warn when it
is implicitly casted to a const int array. Just add a correctly
typed pointer instead to prevent these casts and hence the warnings.

Cc: Troy Kisky <troy.kisky@boundarydevices.com>
Cc: Stefano Babic <sbabic@denx.de>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index bf39a51..948e1fc 100644
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -33,7 +33,7 @@
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	const int (*coeff)[5][3];
 };
 
 #define SYNC_WAVE 0