libunwindstack links libdexfile_support statically now.

Test: Boot
Test: mmm system/bt/gd
Test: gd/cert/run --rhost --clean
  (some errors and hangs eventually, but no difference from before this
  CL: http://go/paste/5965220192190464)
Tag: #refactor
Bug: 143978909
Change-Id: Ib6558a0e9e35bfb4d33cb890d64693d6c80d85df