arm64: zynqmp: add tool to convert PMU config object .c to binary

The recently-added ZYNQMP_SPL_PM_CFG_OBJ_FILE option allows SPL to load a
PMUFW configuration object from a binary blob. However the configuration
object is produced by Xilinx proprietary tools as a C source file and no
tool exists to easily convert it to a binary blob in an embedded Linux
build system for U-Boot to use.

Add a simple Python script to do the conversion.

It is definitely not a complete C language parser, but it is enough to
parse the known patterns generated by Xilinx tools, including:

 - defines
 - literal integers, optionally with a 'U' suffix
 - bitwise OR between them

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>