wl18xx: increase Rx descriptors for PG2
wl18xx: increase Rx descriptors for PG2

New PG2 firmwares have additional Rx descriptors.

Add a module parameter to manually set the number of Rx descriptors for
older versions (PG1). We cannot discriminate based on chip-id, since
this value must be set on probe.

Signed-off-by: Arik Nemtsov <1a5d131848a166677cc209f94fa988cee9378c32@wizery.com>
Signed-off-by: Luciano Coelho <d1ef580865f8eb2e1d1c65bc406aba322cc98f3e@ti.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas