[SCSI] ufshcd-pci: release ioremapped region during removing driver

Before commit 2953f850 ("[SCSI] ufs:
use devres functions for ufshcd"), UFSHCI register was ioremapped by
each glue-driver (ufshcd-pltfrm and ufshcd-pci) during probing and it
was iounmapped by core-driver during removing driver.  The commit
converted ufshcd-pltfrm to use devres functions, but it didn't convert
ufshcd-pci.

Therefore, the change causes ufshcd-pci driver not to iounmap UFSHCI
register region during removing driver.  This fixes it by converting
ufshcd-pci to use devres functions.

Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>