Prevents linking issues with LLVM 7.0.

Bug b/115344057

Change-Id: I7270c2bcf6095b1ec9911074b3119f87680a7cad
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/28168
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>