ata: libahci_platform: move port_map parameters into the AHCI structure

This patch moves force_port_map and mask_port_map into the
ahci_host_priv structure. This allows to modify them into the AHCI
framework. This is needed by the new dt bindings representing ports as
the port_map mask is computed automatically.

Parameters modifying force_port_map, mask_port_map and flags have been
removed from the ahci_platform_init_host() function, and inputs in the
ahci_host_priv structure are now directly filed.

Signed-off-by: Antoine Ténart <antoine.tenart@free-electrons.com>
Signed-off-by: Tejun Heo <tj@kernel.org>