EDAC/amd64: Remove redundant assignment to variable ret in hw_info_get()

The variable ret is being assigned with a value that is never read
and it is being updated later with a new value. The initialization is
redundant so remove it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200429154847.287001-1-colin.king@canonical.com