EDAC, amd64: Add x86cpuid sanity check during init

Match one of the devices in amd64_cpuids[] before loading the module.
This is an additional sanity check against users trying to load
amd64_edac_mod on unsupported systems.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1485537863-2707-9-git-send-email-Yazen.Ghannam@amd.com
[ Get rid of err_ret label, make it a bit more readable this way. ]
Signed-off-by: Borislav Petkov <bp@suse.de>

drivers/edac/amd64_edac.c

@@ -3440,8 +3440,11 @@ static int __init amd64_edac_init(void)
 	int err = -ENODEV;
 	int i;
 
+	if (!x86_match_cpu(amd64_cpuids))
+		return -ENODEV;
+
 	if (amd_cache_northbridges() < 0)
-		goto err_ret;
+		return -ENODEV;
 
 	opstate_init();
 
@@ -3497,7 +3500,6 @@ err_free:
 	kfree(ecc_stngs);
 	ecc_stngs = NULL;
 
-err_ret:
 	return err;
 }