qcacld-3.0: Consider host and firmware capa for NAN separate vdev

Firmware advertises the NAN separate vdev capability through
the service capability wmi_service_nan_vdev and host advertises
through the ini param nan_separate_iface_support. Both of the
capabilities must be checked to support the NAN separate vdev
support. Define an API to check both the capabilities and made
the individual capability APIs static. So that individual APIs
are not accessed outside this common API. Use this API to
know the support. This is to avoid any possible misses in
checking the support.
For example, NAN vdev id is fetched from the NAN enable
response message received from firmware only based on
firmware capability in nan_handle_enable_rsp. If firmware
supports the feature and ini is set to 0, then vdev id might
be invalid as it's fetched from the NAN enable response
without considering host capability. If either firmware or
host doesn't support NAN separate vdev feature, firmware
creates vdev and it may not fill the vdev id in NAN enable
response. Host shall use NAN_PSEUDO_VDEV_ID then.
So, consider NAN separate vdev feature as supported only if
both host and firmware support.
Also fetch the firmware capability to support NAN separate vdev
when wma_rx_service_ready_ext_event is received and update to NAN
psoc priv object.

Change-Id: I50e76fbe17befb28a5262fc26f5675b67f4d21f2
CRs-Fixed: 2650354