Fixed panic when getting socket stats with go 1.6
Fixed panic when getting socket stats with go 1.6

xuzhaokui/gopacket,adriantam/gopacket,skyportsystems/gopacket,levigross/gopacket,google/gopacket,vtolstov/gopacket,rouzier/gopacket,skyportsystems/gopacket,google/gopacket,LrsK/gopacket,LrsK/gopacket,rouzier/gopacket,skyportsystems/gopacket,LrsK/gopacket,ross-williams/gopacket,google/gopacket,ross-williams/gopacket,vtolstov/gopacket,rouzier/gopacket,adriantam/gopacket,ross-williams/gopacket,levigross/gopacket,xuzhaokui/gopacket,xuzhaokui/gopacket,levigross/gopacket,adriantam/gopacket,vtolstov/gopacket