Tegra194: SiP: Fix Rule 8.4 and Rule 10.4 violation

Rule 8.4, A compatible declaration shall be visible when an object
  or function with external linkage is defined.

Add function delaration to the header file.
Add suffix U to the unsigned constant define.

Change-Id: I54eba913a5fa38e4fdf3655931dc421d9510c691
Signed-off-by: Anthony Zhou <anzhou@nvidia.com>
diff --git a/plat/nvidia/tegra/soc/t194/drivers/include/mce_private.h b/plat/nvidia/tegra/soc/t194/drivers/include/mce_private.h
index 32e7a53..966c90b 100644
--- a/plat/nvidia/tegra/soc/t194/drivers/include/mce_private.h
+++ b/plat/nvidia/tegra/soc/t194/drivers/include/mce_private.h
@@ -50,6 +50,9 @@
 int32_t nvg_is_sc7_allowed(void);
 int32_t nvg_online_core(uint32_t core);
 int32_t nvg_update_ccplex_gsc(uint32_t gsc_idx);
+int32_t nvg_roc_clean_cache(void);
+int32_t nvg_roc_flush_cache(void);
+int32_t nvg_roc_clean_cache_trbits(void);
 int32_t nvg_enter_cstate(uint32_t state, uint32_t wake_time);
 
 void nvg_set_request_data(uint64_t req, uint64_t data);