net_sched: act_police: add 2 new attributes to support police 64bit rate and peakrate

For high speed adapter like Mellanox CX-5 card, it can reach upto
100 Gbits per second bandwidth. Currently htb already supports 64bit rate
in tc utility. However police action rate and peakrate are still limited
to 32bit value (upto 32 Gbits per second). Add 2 new attributes
TCA_POLICE_RATE64 and TCA_POLICE_RATE64 in kernel for 64bit support
so that tc utility can use them for 64bit rate and peakrate value to
break the 32bit limit, and still keep the backward binary compatibility.

Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Signed-off-by: David Dai <zdai@linux.vnet.ibm.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>