ixgbe: Initialize 64-bit stats seqcounts

On 32-bit hosts and with CONFIG_DEBUG_LOCK_ALLOC we should be seeing a
lockdep splat indicating this seqcount is not correctly initialized, fix
that.

Fixes: 4197aa7b ("ixgbevf: provide 64 bit statistics")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>