scons: Add instrumentation component libraries to linking on llvm-3.2.

llvm-3.2svn r160587 moved createBoundsCheckingPass from
lib/Transforms/Scalar to lib/Transforms/Instrumentation.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: José Fonseca <jfonseca@vmware.com>

scons/llvm.py

@@ -180,6 +180,9 @@ def generate(env):
 
             components = ['engine', 'bitwriter', 'x86asmprinter']
 
+            if llvm_version >= distutils.version.LooseVersion('3.2'):
+                components.append('instrumentation')
+
             if llvm_version >= distutils.version.LooseVersion('3.1'):
                 components.append('mcjit')