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>