be2net: use be_max_vfs() macro to access max-vfs

max-vfs value must be accessed via the macro be_max_vfs(adapter).
The earlier patch "create optimal number of queues on SR-IOV config"
by mistake, did not use this macro. This patch fixes it.

fixes: bec84e6b

 ("be2net: create optimal number of queues on SR-IOV config")
Signed-off-by: Vasundhara Volam <vasundhara.volam@emulex.com>
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>