fix(zynqmp): resolve misra R8.4 warnings

MISRA Violation: MISRA-C:2012 R.8.4
- Function definition does not have a visible prototype.

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@xilinx.com>
Change-Id: I50a2c1adf2e099217770ac665f135302f990b162

plat/xilinx/zynqmp/plat_psci.c

@@ -19,9 +19,9 @@
 #include "pm_api_sys.h"
 #include "pm_client.h"
 
-uintptr_t zynqmp_sec_entry;
+static uintptr_t zynqmp_sec_entry;
 
-void zynqmp_cpu_standby(plat_local_state_t cpu_state)
+static void zynqmp_cpu_standby(plat_local_state_t cpu_state)
 {
 	VERBOSE("%s: cpu_state: 0x%x\n", __func__, cpu_state);
 
@@ -171,7 +171,7 @@ static void __dead2 zynqmp_system_reset(void)
 	}
 }
 
-int zynqmp_validate_power_state(unsigned int power_state,
+static int zynqmp_validate_power_state(unsigned int power_state,
 				psci_power_state_t *req_state)
 {
 	VERBOSE("%s: power_state: 0x%x\n", __func__, power_state);
@@ -194,7 +194,7 @@ int zynqmp_validate_power_state(unsigned int power_state,
 	return PSCI_E_SUCCESS;
 }
 
-void zynqmp_get_sys_suspend_power_state(psci_power_state_t *req_state)
+static void zynqmp_get_sys_suspend_power_state(psci_power_state_t *req_state)
 {
 	req_state->pwr_domain_state[PSCI_CPU_PWR_LVL] = PLAT_MAX_OFF_STATE;
 	req_state->pwr_domain_state[1] = PLAT_MAX_OFF_STATE;

plat/xilinx/zynqmp/sip_svc_setup.c

@@ -53,7 +53,7 @@ static int32_t sip_svc_setup(void)
  * Handler for all SiP SMC calls. Handles standard SIP requests
  * and calls PM SMC handler if the call is for a PM-API function.
  */
-uintptr_t sip_svc_smc_handler(uint32_t smc_fid,
+static uintptr_t sip_svc_smc_handler(uint32_t smc_fid,
 			      u_register_t x1,
 			      u_register_t x2,
 			      u_register_t x3,