This patch sets the quirk_avoids_skb_reserve flag to improve performance
of a network gadget driver (e.g. f_ncm.c) if USB-DMAC is used.

For example (on r8a7795 board + f_ncm.c + iperf udp mode / receiving):
  - without this patch:  90.3 Mbits/sec
  - with    this patch: 273   Mbits/sec
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>