QL(quantity limiting) means that hardware supports the interrupt
coalesce based on the frame quantity.  QL can be configured when
int_ql_max in device's specification is non-zero, so add support
to configure it. Also, rename two coalesce init function to fit
their purpose.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>