PCI: mobiveil: Add configured inbound windows counter

Current code only keeps track of the number of outbound windows
configured but it does not for inbound windows. Add a counter
to keep track of initialized inbound windows.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Minghuan Lian <Minghuan.Lian@nxp.com>
Reviewed-by: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>