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

This pulls in the following LLVM changes:

d7d2a80: (kschimpf@google.com) Remove obsolete NaClBitcodeMunger editing constants.
4c20e87: (kschimpf@google.com) Add abilities to generate bitcode buffers from munged bitcode.
f46b724: (kschimpf@google.com) Add (unsupported experimental) feature allowing byte aligned bitcode.
d0089f0: (mseaborn@chromium.org) Cherry-pick r234714: [MC] Write padding into fragments when -mc-relax-all flag is used

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4164
BUG= https://code.google.com/p/nativeclient/issues/detail?id=4063
TEST= PNaCl toolchain trybots
TBR=dschuff@chromium.org

Review URL: https://codereview.chromium.org/1126183003

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