gpu: nvgpu: Refactor PERF VFE unit

-Created ucode_perf_vfe_inf.h and moved all VFE
 interface structs and MACROs into this header
-Created nvgpu_clk_fll_get_fmargin_idx to get
 freq margin index
-Created nvgpu_vfe_var_get_s_param to read s_param
-Removed MACROs and header includes which are
 not needed

NVGPU-4448

Change-Id: I89f946d555bcbc7823665d2a5a761049f7a5e963
Signed-off-by: rmylavarapu <rmylavarapu@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2260150
GVS: Gerrit_Virtual_Submit
Reviewed-by: Mahantesh Kumbar <mkumbar@nvidia.com>
Reviewed-by: Vijayakumar Subbu <vsubbu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/pmu/perf/perf_ps35.c

@@ -29,8 +29,6 @@
 #include <nvgpu/pmu/perf.h>
 #include <nvgpu/pmu/cmd.h>
 
-#include "pmu_perf.h"
-
 static int pmu_set_boot_clk_runcb_fn(void *arg)
 {
 	struct gk20a *g = (struct gk20a *)arg;