x86/mce/amd: Fix threshold limit reset

x86/mce/amd: Fix threshold limit reset

commit 5f6e3b720694ad771911f637a51930f511427ce1 upstream.

The MCA threshold limit must be reset after servicing the interrupt.

Currently, the restart function doesn't have an explicit check for this.  It
makes some assumptions based on the current limit and what's in the registers.
These assumptions don't always hold, so the limit won't be reset in some
cases.

Make the reset condition explicit. Either an interrupt/overflow has occurred
or the bank is being initialized.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250624-wip-mca-updates-v4-4-236dd74f645f@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>