x86/mm/pat, drivers/infiniband/ipath: Replace WARN() with pr_warn()

WARN() may confuse users, fix that. ipath_init_one() is part the
device's probe so this would only be triggered if a
corresponding device was found.

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andy@silverblocksystems.net
Cc: benh@kernel.crashing.org
Cc: bp@suse.de
Cc: dan.j.williams@intel.com
Cc: jkosina@suse.cz
Cc: julia.lawall@lip6.fr
Cc: luto@amacapital.net
Cc: mchehab@osg.samsung.com
Link: http://lkml.kernel.org/r/1437167245-28273-2-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>