[SCSI] sd: update index allocation and use ida instead of idr
[SCSI] sd: update index allocation and use ida instead of idr

Update index allocation as follows.

* sd_index_idr is used only for ID allocation and mapping
  functionality is not used.  Use more memory efficient ida instead.

* idr and ida have their own locks inside them and don't need them for
  operation.  Drop it.

* index wasn't freed if probing failed after index allocation.  fix
  it.

* ida allocation should be repeated if it fails with -EAGAIN.

Signed-off-by: Tejun Heo <546b05909706652891a87f7bfe385ae147f61f91@kernel.org>
Signed-off-by: James Bottomley <407b36959ca09543ccda8f8e06721c791bc53435@HansenPartnership.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas