EDAC: Add EDAC driver for ARM Cortex A72 cores

EDAC: Add EDAC driver for ARM Cortex A72 cores

The driver is designed to support error detection and reporting for
Cortex A72 cores, specifically within their L1 and L2 cache systems.
The errors are detected by reading CPU/L2 memory error syndrome
registers.

Unfortunately there is no robust way to inject errors into the caches,
so this driver doesn't contain any code to actually test it. It has
been tested though with code taken from an older version [1] of this
driver. For reasons stated in thread [1], the error injection code is
not suitable for mainline, so it is removed from the driver.

  [1] https://lore.kernel.org/all/1521073067-24348-1-git-send-email-york.sun@nxp.com/#t

  [ bp: minor touchups. ]

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Co-developed-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/1752714390-27389-2-git-send-email-vijayb@linux.microsoft.com