xilinx: common: Separate display cpu info function

Move the print_cpuinfo function of CONFIG_DISPLAY_CPUINFO into its own
source file to support reuse by other board vendors.

Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
Link: https://lore.kernel.org/r/20220620163650.18756-10-stefan.herbrechtsmeier-oss@weidmueller.com


Signed-off-by: Michal Simek <michal.simek@amd.com>