cnss2: Fix PCIe D3hot for WLAN suspend

Setting D3hot is newly added for Napier platform. And system hang is
observed on legacy Rome platform. In previous implementations for Rome
PCIe platforms, setting D3hot is not needed.

Fix is to not set D3hot for legacy platforms.

Change-Id: I1fce39eff4aa674553a214e7d0f99a81b0e6b93d
CRs-Fixed: 2255872
Signed-off-by: Jia Ding <jiad@codeaurora.org>