EDAC/amd64: Remove unneeded breaks

A break is not needed if it is preceded by a return.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Robert Richter <rric@kernel.org>
Link: https://lkml.kernel.org/r/20201019193524.13391-1-trix@redhat.com