gpu: nvgpu: Segregate clk unit members based on their accessibility

Current clk unit has multiple header files under include folder.
This has combination of public struct which is accessed outside the
unit and private struct which is accessed within clk unit.
This patch segregates them based on their accessibility.
All private items are moved into ucode_clk_inf.h from include which only
clk can access.
All public items are moved into include/clk.h which other units can
access and removed the clk_xxx.h files

NVGPU-4689

Change-Id: I469270ae539e09a3f6fe6187207791732407863e
Signed-off-by: Abdul Salam <absalam@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2298220
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/pmu/clk/clk_prog.c

@@ -29,7 +29,6 @@
 #include <nvgpu/pmu/boardobjgrp_classes.h>
 #include <nvgpu/string.h>
 #include <nvgpu/pmu/clk/clk.h>
-#include <nvgpu/pmu/clk/clk_vf_point.h>
 
 #include "ucode_clk_inf.h"
 #include "clk_prog.h"