Split out isa probing into a helper of it's own. Error handling is
cleaned up, but errors are not propagated yet. Also enclose the isa
probe under the proper CONFIG_ISA symbol instead of the !IA64 hack.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>