brcmfmac: add RSDB condition when setting interface combinations

With firmware RSDB feature
1. The maximum support interface is four.
2. The maximum difference channel is two.
3. The maximum interfaces of {station/p2p client/AP} are two.
4. The maximum interface of p2p device is one.

Signed-off-by: Wright Feng <wright.feng@cypress.com>
Signed-off-by: Soeren Moch <smoch@web.de>
Reviewed-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>