PNaCl: Update llvm revision in pnacl/COMPONENT_REVISIONS
PNaCl: Update llvm revision in pnacl/COMPONENT_REVISIONS

This pulls in the following LLVM change:

fd91d18: (jfb@chromium.org) Propagate function and function argument attributes to simplified functions. Do the same for call instructions. Bitcast pointer arguments whose pointer element type changes due to promotion. Bitcast functions that get simplified. Bitcast constant instruction operands.

BUG=none
TEST= PNaCl toolchain trybots

Review URL: https://codereview.chromium.org/1317683003

sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client