Removing the 'select SCSI_SAS_LIBSAS' statement in Kconfig resulted in a
link failure in configurations that have hisi_sas built-in but libsas as
a loadable module:

drivers/scsi/built-in.o: In function `hisi_sas_scan_finished':
hisi_sas_main.c:(.text+0x37ce9): undefined reference to `sas_drain_work'
drivers/scsi/built-in.o: In function `hisi_sas_slave_configure':
hisi_sas_main.c:(.text+0x37d17): undefined reference to `sas_slave_configure'
hisi_sas_main.c:(.text+0x37d40): undefined reference to `sas_change_queue_depth'
drivers/scsi/built-in.o: In function `hisi_sas_remove':

All other libsas users have the 'select' statement, so we should do the
same here for consistency. For all I can tell, the patch that added the
sata softreset does not actually introduce a dependency on SCSI_SAS_ATA
but instead adds calls into libata itself, so we can express that with a
more specific dependency.

We cannot have 'select SCSI_SAS_LIBSAS; depends on SCSI_SAS_ATA' as that
would cause a dependency loop.

Fixes: 7c594f04 ("scsi: hisi_sas: add softreset function for SATA disk")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>