PCI: mobiveil: Remove the flag MSI_FLAG_MULTI_PCI_MSI

The Mobiveil internal MSI controller requires separate target addresses,
one per MSI vector; this is clearly incompatible with the Multiple MSI
feature, which requires the same target address for all vectors
requested by an endpoint (ie the Message Address field in the MSI
Capability structure), so the multi MSI feature is clearly not
supported by the host controller driver.

Remove the flag MSI_FLAG_MULTI_PCI_MSI and with it multi MSI support,
fixing the misconfiguration.

Fixes: 1e913e58 ("PCI: mobiveil: Add MSI support")
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Minghuan Lian <Minghuan.Lian@nxp.com>