For new MM contexts, the ra_id was correctly obtained from the ue_ctx, but in
case an MM ctx is re-used and the ra_id changed, the new ra_id was not copied
to the MM context; instead, the ra_id was overwritten with uninitialized data.
Always initialize the local ra_id variable from the ue_ctx->ra_id for Iu
connections; it is used further below to update the ctx->ra_id.
For the case of a brand new Iu MM ctx, the ctx->ra_id then gets initialized a
second time. We could technically drop the init in sgsn_mm_ctx_alloc_iu(), but
it doesn't hurt either way.
Fixes: CID#57936
Change-Id: Ia06458758362e76925690b1757d8ced95e9609e4
Neels Hofmeyr
eb52aad198