scsi: target: core: Generate correct identifiers for PR OUT transport IDs

scsi: target: core: Generate correct identifiers for PR OUT transport IDs

Fix target_parse_pr_out_transport_id() to return a string representing
the transport ID in a human-readable format (e.g., naa.xxxxxxxx...)  for
various SCSI protocol types (SAS, FCP, SRP, SBP).

Previously, the function returned a pointer to the raw binary buffer,
which was incorrectly compared against human-readable strings, causing
comparisons to fail.  Now, the function writes a properly formatted
string into a buffer provided by the caller.  The output format depends
on the transport protocol:

* SAS: 64-bit identifier, "naa." prefix.
* FCP: 64-bit identifier, colon separated values.
* SBP: 64-bit identifier, no prefix.
* SRP: 128-bit identifier, "0x" prefix.
* iSCSI: IQN string.

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Link: https://lore.kernel.org/r/20250714133738.11054-1-mlombard@redhat.com
Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>