[PATCH] PCI: fix stale PCI pm docs

This fixes u32 vs. pm_message_t confusion in documentation, and
removes references to no-longer-existing (*save_state), too. With
exception of USB (I hope David will fix/apply my patch), this should
fix last piece of this confusion... famous last words.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>