gpu: nvgpu: Add gr_priv header file

Move nvgpu_gr structure to private file gr_priv.h
Include the private file where gr variables are used.

JIRA NVGPU-3132
JIRA NVGPU-3079

Change-Id: Ib26ca5c5cb25fd8dd013a7c643278efc34aa55d4
Signed-off-by: Vinod G <vinodg@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2098021
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/perf/cyclestats_snapshot.c

@@ -39,6 +39,8 @@
 #include <nvgpu/gk20a.h>
 #include <nvgpu/cyclestats_snapshot.h>
 
+#include "common/gr/gr_priv.h"
+
 /* check client for pointed perfmon ownership */
 #define CONTAINS_PERFMON(cl, pm)				\
 		((cl)->perfmon_start <= (pm) &&			\