msm: ipa: eth: Use L2_802_1Q IPA header type in VLAN mode

Use IPA header type of IPA_HDR_L2_802_1Q in VLAN mode operation in order
to support IPA VLAN Lan-to-Lan configuration.

Change-Id: Iebf7bbb75a8107176a193640cc94f89e9edc116b
Signed-off-by: Jinesh K. Jayakumar <jineshk@codeaurora.org>