x86/PCI: use pr_level() to replace printk(KERN_LEVEL)

Script checkpatch.pl recommends to replace printk(KERN_LVL) with pr_lvl(),
so do it.

Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c
index c206521..d4ebd07 100644
--- a/arch/x86/pci/mmconfig_64.c
+++ b/arch/x86/pci/mmconfig_64.c
@@ -137,8 +137,7 @@
 {
 	cfg->virt = mcfg_ioremap(cfg);
 	if (!cfg->virt) {
-		printk(KERN_ERR PREFIX "can't map MMCONFIG at %pR\n",
-		       &cfg->res);
+		pr_err(PREFIX "can't map MMCONFIG at %pR\n", &cfg->res);
 		return -ENOMEM;
 	}