In STA-SAP config, IPA offload is enabled only when first
client is connected to SAP. This is OK for MSM platforms.
But for MDM platforms, this is not the case. There's STA
tethering cases, where traffic is routed between STA and
USB tethering devices while SAP is idle and no wifi clients
are connected to SAP. In such case, IPA offload needs to
be enabled for STA to promote performance.
Fix is to use available MDM_PLATFORM marco and STA only IPA
support is decided upon driver build time.
Change-Id: If2bc016aa941f2c0651a2669f1169e631208326b
CRs-Fixed: 2433608
72b69a952e