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/zynqmp/zynqmp_ipi.c b/plat/xilinx/zynqmp/zynqmp_ipi.c
index c7d2c08..439bd6f 100644
--- a/plat/xilinx/zynqmp/zynqmp_ipi.c
+++ b/plat/xilinx/zynqmp/zynqmp_ipi.c
@@ -85,7 +85,7 @@
 };
 
 /**
- * zynqmp_ipi_config_table_init() - Initialize ZynqMP IPI configuration data
+ * zynqmp_ipi_config_table_init() - Initialize ZynqMP IPI configuration data.
  *
  */
 void zynqmp_ipi_config_table_init(void)