wil6210: remove 3-MSI support

In the recent kernel versions, multiple MSI is not well supported.
In particular, it is not supported on x86 and ARM architectures.
Also, internal interrupt handling logic is simpler and
more effective when using single interrupt.

Remove support for 3 MSI, convert module parameter
"use_msi" from int with range [0,1,3] to boolean.

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>