Update libbcc for rebase to LLVM r235153

Some changes related to GEP may impact us in the future:
- GEP constructors take an additional argument - the pointee type of the
  resulting pointer.  Update bitcode readers accordingly.  They take
  nullptr for now.  This behavior should be retained at least for 3.x.
- Likewise, CreateStructGEP and CreateConstInBoundsGEP2_32 need the
  pointee type argument.  Passing nullptr for the extra argument for
  now.  According to commit message in r233938, passing nullptr may not
  work in the future.  Unlike the BitcodeReaders, we can pass the right
  pointee type here.  b/20886457 is created to track this issue.

Change-Id: I2450da1c36470fb9defd387d74360480c3e4bd2f
(cherry picked from commit 98137cca7eebca946b869b010fef2821c9bf4971)
5 files changed