msm: ipa: support GRO feature for netmgrd

For this GRO feature, IPA-driver should not
de-aggregate the pkt received from modem, also
no need to attach status. Also netmgrd will
call ioctl to wan-driver to indeicate when
this feature will be enable.

Change-Id: I54e016312631b6398c6608a5981ff238c9957944
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>