gallivm: drop LLVM<3.3 code paths as no build system allows that

Suggested-by: Michel Dänzer <mdaenzer@redhat.com>
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
23 jobs for !1565 with llvm-version in 14 minutes and 22 seconds (queued for 2 seconds)
merge request