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/common/plat_startup.c b/plat/xilinx/common/plat_startup.c
index 007c045..d034e00 100644
--- a/plat/xilinx/common/plat_startup.c
+++ b/plat/xilinx/common/plat_startup.c
@@ -55,11 +55,12 @@
 #define FSBL_FLAGS_A53_3		3U
 
 /**
- * @partition: Pointer to partition struct
+ * get_fsbl_cpu() - Get the target CPU for partition.
+ * @partition: Pointer to partition struct.
  *
- * Get the target CPU for @partition.
+ * Return: FSBL_FLAGS_A53_0, FSBL_FLAGS_A53_1, FSBL_FLAGS_A53_2 or
+ *         FSBL_FLAGS_A53_3.
  *
- * Return: FSBL_FLAGS_A53_0, FSBL_FLAGS_A53_1, FSBL_FLAGS_A53_2 or FSBL_FLAGS_A53_3
  */
 static int32_t get_fsbl_cpu(const struct xfsbl_partition *partition)
 {
@@ -69,11 +70,11 @@
 }
 
 /**
- * @partition: Pointer to partition struct
+ * get_fsbl_el() - Get the target exception level for partition.
+ * @partition: Pointer to partition struct.
  *
- * Get the target exception level for @partition.
+ * Return: FSBL_FLAGS_EL0, FSBL_FLAGS_EL1, FSBL_FLAGS_EL2 or FSBL_FLAGS_EL3.
  *
- * Return: FSBL_FLAGS_EL0, FSBL_FLAGS_EL1, FSBL_FLAGS_EL2 or FSBL_FLAGS_EL3
  */
 static int32_t get_fsbl_el(const struct xfsbl_partition *partition)
 {
@@ -83,11 +84,11 @@
 }
 
 /**
- * @partition: Pointer to partition struct
+ * get_fsbl_ss() - Get the target security state for partition.
+ * @partition: Pointer to partition struct.
  *
- * Get the target security state for @partition.
+ * Return: FSBL_FLAGS_NON_SECURE or FSBL_FLAGS_SECURE.
  *
- * Return: FSBL_FLAGS_NON_SECURE or FSBL_FLAGS_SECURE
  */
 static int32_t get_fsbl_ss(const struct xfsbl_partition *partition)
 {
@@ -97,11 +98,11 @@
 }
 
 /**
- * @partition: Pointer to partition struct
+ * get_fsbl_endian() - Get the target endianness for partition.
+ * @partition: Pointer to partition struct.
  *
- * Get the target endianness for @partition.
+ * Return: SPSR_E_LITTLE or SPSR_E_BIG.
  *
- * Return: SPSR_E_LITTLE or SPSR_E_BIG
  */
 static int32_t get_fsbl_endian(const struct xfsbl_partition *partition)
 {
@@ -117,11 +118,11 @@
 }
 
 /**
- * @partition: Pointer to partition struct
+ * get_fsbl_estate() - Get the target execution state for partition.
+ * @partition: Pointer to partition struct.
  *
- * Get the target execution state for @partition.
+ * Return: FSBL_FLAGS_ESTATE_A32 or FSBL_FLAGS_ESTATE_A64.
  *
- * Return: FSBL_FLAGS_ESTATE_A32 or FSBL_FLAGS_ESTATE_A64
  */
 static int32_t get_fsbl_estate(const struct xfsbl_partition *partition)
 {
@@ -131,16 +132,17 @@
 }
 
 /**
- * Populates the bl32 and bl33 image info structures
- * @bl32:	BL32 image info structure
- * @bl33:	BL33 image info structure
- * tfa_handoff_addr:  TF-A handoff address
+ * fsbl_tfa_handover() - Populates the bl32 and bl33 image info structures.
+ * @bl32: BL32 image info structure.
+ * @bl33: BL33 image info structure.
+ * @tfa_handoff_addr: TF-A handoff address.
  *
  * Process the handoff parameters from the FSBL and populate the BL32 and BL33
  * image info structures accordingly.
  *
  * Return: Return the status of the handoff. The value will be from the
  *         fsbl_handoff enum.
+ *
  */
 enum fsbl_handoff fsbl_tfa_handover(entry_point_info_t *bl32,
 					entry_point_info_t *bl33,