HTT_TX_HL_NEEDED_HEADROOM
if (skb_headroom(msdu) < HTT_TX_HL_NEEDED_HEADROOM) {
skb_headroom(msdu), HTT_TX_HL_NEEDED_HEADROOM);
msdu = skb_realloc_headroom(msdu, HTT_TX_HL_NEEDED_HEADROOM);