bnx2x: Don't disable/enable SR-IOV when loading

Current bnx2x implementation controls the number of VFs only by
standard sysfs support, and will reject setting the number of VFs
when the PF is not loaded.
As a result, there is no need to schedule a delayed work to enable
SR-IOV when PF is loaded, as the number of VFs at that point
must be 0.

Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>