drivers: edac: Add support to re-enable edac on cpu hotplug

EDAC ppi interrupts get disabled on cpu hotplug.
Add support to re-enable edac ppi post cpu comes online
during hotplug.

Change-Id: I51455c0134634f03b5e4e83eca915b794dd85067
Signed-off-by: Mayank Grover <groverm@codeaurora.org>