The uppermost bit of COMPREHENSION-TLV tags indicates whether the
recipient is required to "comprehend" that IE or not. So every IE
actually has two tag values: one with and one without that bit set.
As all our existing TLV definitions of COMPR_TLV_IE have that bit set,
let's assume this is the default, but use the same definition also for
the situation where that bit is not set.
Change-Id: I58d04ec13be0c12d9fb8cb3d5a0480d0defb6c95