ahci: drop unused board_ahci_noncq

Since commit 66a7cbc3 ("ahci: disable MSI instead of NCQ on Samsung
pci-e SSDs on macbooks") there is not a single entry in ahci_pci_tbl
which uses board_ahci_noncq.

Since this is dead code, let's remove it.
We cannot remove AHCI_HFLAG_NO_NCQ, as this flag is still used by other
boards.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Niklas Cassel <cassel@kernel.org>