qtnfmac_pcie: indicate pearl-specific structures by their names

In preparation to extract common PCIe driver state, indicate
PEARL-specific structures by their name and move them to pearl-specific
source file.

Signed-off-by: Igor Mitsyanko <igor.mitsyanko.os@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>