x86: rename iommu_num_pages function to iommu_nr_pages

This series of patches re-introduces the iommu_num_pages function so that
it can be used by each architecture specific IOMMU implementations.  The
series also changes IOMMU implementations for X86, Alpha, PowerPC and
UltraSparc.  The other implementations are not yet changed because the
modifications required are not obvious and I can't test them on real
hardware.

This patch:

This is a preparation patch for introducing a generic iommu_num_pages function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>