This patch creates a new 'supported' driver for Seagate (STX) FC and
iSCSI arrays by renaming and re-enabling the old 'unsupported' dothill
driver. Other than marking the driver as 'supported', this patch
contains no changes in functionality except for multiattach fixes from
change I47f02729437cabab92ccc553a4c60d0c0a796952 needed to pass CI and
deprecation of vendor-specific options requested by the core team.
Other drivers which referenced the dothill driver are modified to use
the Seagate class names, so users of those drivers will not be affected
except for option-deprecation warnings.
Change-Id: I3115ae296ae6b5702c7a8fa39249b8735542e17e
e18f05e735