msm: ipa3: Update MPLS DL Vlan tag array to use 16 bits

MPLS GRE supports 12 bits up to 4094 vlans. 16 bits
can support this max value while 8 bits will support
only 254 values. Without this fix, vlans 255-4094 are
not usable.

Change-Id: I582f0186b2d1042e394b75762793b6234b0f097e
Signed-off-by: Michael Adisumarta <quic_madisuma@quicinc.com>