be2net: remove a line of code that has no effect

This patch removes a line of code that changes adapter->recommended_prio
value followed by yet another assignment.
Also, the variable is used to store the vlan priority value that is already
shifted to the PCP bits position in the vlan tag format. Hence, the name of
this variable is changed to recommended_prio_bits.

Signed-off-by: Sathya Perla <sathya.perla@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>