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

This pulls in the following LLVM changes:

c8fa431: (dschuff@chromium.org) Auto-sandboxing: ignore instructions with no register memory operands
53d3a6c: (dschuff@chromium.org) Auto-sandboxing: use ADDrr instead of ADDrsi when emitting ARM sandbox instrs
dd160f2: (phosek@chromium.org) Do not create init/fini array symbols unless needed
365a749: (petar.jovanovic@rt-rk.com) [MIPS] Add ExpandVarArgs pass to mipsel-nacl-clang

BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4335
TEST= PNaCl toolchain trybots

Review URL: https://codereview.chromium.org/1667363002

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