resource_size_t is 64 bits on pseries

Gets rid of these warnings:

arch/powerpc/platforms/pseries/iommu.c: In function 'pci_dma_bus_setup_pSeries':
arch/powerpc/platforms/pseries/iommu.c:391: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'resource_size_t'
arch/powerpc/platforms/pseries/iommu.c:417: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'resource_size_t'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>