chore(xilinx): follow kernel doc format for functional documentation

For TF-A, there is no format specified for functional documentation.
For AMD-Xilinx platforms, following kernel-doc format for the functional
documentation to make sure AMD-xilinx documentation is align with
actual code.

For example use kernel-doc from linux to call:
<linux>/scripts/kernel-doc -man -v 1 >/dev/null file...

Signed-off-by: Prasad Kummari <prasad.kummari@amd.com>
Change-Id: Idcc9def408b6c8da35b36f67ef82fc00890e998c
diff --git a/plat/xilinx/versal/pm_service/pm_client.c b/plat/xilinx/versal/pm_service/pm_client.c
index af5263d..9ad21a1 100644
--- a/plat/xilinx/versal/pm_service/pm_client.c
+++ b/plat/xilinx/versal/pm_service/pm_client.c
@@ -51,10 +51,11 @@
 const struct pm_proc *primary_proc = &pm_procs_all[0];
 
 /**
- * irq_to_pm_node_idx - Get PM node index corresponding to the interrupt number
- * @irq:	Interrupt number
+ * irq_to_pm_node_idx - Get PM node index corresponding to the interrupt number.
+ * @irq: Interrupt number
  *
- * Return:	PM node index corresponding to the specified interrupt
+ * Return: PM node index corresponding to the specified interrupt.
+ *
  */
 enum pm_device_node_idx irq_to_pm_node_idx(uint32_t irq)
 {
@@ -172,11 +173,14 @@
 }
 
 /**
- * pm_client_suspend() - Client-specific suspend actions
+ * pm_client_suspend() - Client-specific suspend actions.
+ * @proc: processor which need to suspend.
+ * @state: desired suspend state.
  *
  * This function should contain any PU-specific actions
  * required prior to sending suspend request to PMU
  * Actions taken depend on the state system is suspending to.
+ *
  */
 void pm_client_suspend(const struct pm_proc *proc, uint32_t state)
 {
@@ -194,10 +198,11 @@
 }
 
 /**
- * pm_client_abort_suspend() - Client-specific abort-suspend actions
+ * pm_client_abort_suspend() - Client-specific abort-suspend actions.
  *
  * This function should contain any PU-specific actions
- * required for aborting a prior suspend request
+ * required for aborting a prior suspend request.
+ *
  */
 void pm_client_abort_suspend(void)
 {
@@ -214,10 +219,11 @@
 }
 
 /**
- * pm_get_cpuid() - get the local cpu ID for a global node ID
- * @nid:	node id of the processor
+ * pm_get_cpuid() - get the local cpu ID for a global node ID.
+ * @nid: node id of the processor.
  *
- * Return: the cpu ID (starting from 0) for the subsystem
+ * Return: the cpu ID (starting from 0) for the subsystem.
+ *
  */
 static uint32_t pm_get_cpuid(uint32_t nid)
 {
@@ -230,10 +236,12 @@
 }
 
 /**
- * pm_client_wakeup() - Client-specific wakeup actions
+ * pm_client_wakeup() - Client-specific wakeup actions.
+ * @proc: Processor which need to wakeup.
  *
  * This function should contain any PU-specific actions
- * required for waking up another APU core
+ * required for waking up another APU core.
+ *
  */
 void pm_client_wakeup(const struct pm_proc *proc)
 {
@@ -254,10 +262,11 @@
 }
 
 /**
- * pm_get_proc() - returns pointer to the proc structure
- * @cpuid:	id of the cpu whose proc struct pointer should be returned
+ * pm_get_proc() - returns pointer to the proc structure.
+ * @cpuid: id of the cpu whose proc struct pointer should be returned.
+ *
+ * Return: pointer to a proc structure if proc is found, otherwise NULL.
  *
- * Return: pointer to a proc structure if proc is found, otherwise NULL
  */
 const struct pm_proc *pm_get_proc(uint32_t cpuid)
 {