EDAC/al-mc-edac: Add Amazon's Annapurna Labs Memory Controller driver

The Amazon's Annapurna Labs Memory Controller EDAC supports ECC capability
for error detection and correction (Single bit error correction, Double
detection). This driver introduces EDAC driver for that capability.

 [ bp: Remove "EDAC" string from Kconfig tristate as it is redundant. ]

Signed-off-by: Talel Shenhar <talel@amazon.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: James Morse <james.morse@arm.com>
Link: https://lkml.kernel.org/r/20200816185551.19108-3-talel@amazon.com