ipr: Fix sync scsi scan

Commit b195d5e2

 ("ipr: Wait to do async scan until scsi host is
initialized") fixed async scan for ipr, but broke sync scan for ipr.

This fixes sync scan back up.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Reported-and-tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>