Stopped bcc from ignoring optimization level

Added in a constructor for RSScript which takes in the compiler
config and derives the optimization level from that rather than
defaulting it to opt level 3. Also added in a statement to catch
a null pointer for the case where the llvm-rs-cc produced bitcode
fails verification.

Change-Id: I6efdab6280a9c389268b5a40dc4a50eb9bc24370
Signed-off-by: Stephen McGroarty <stephen@codeplay.com>
5 files changed