Update gcc revision in tools/REVISIONS
Update gcc revision in tools/REVISIONS

This brings in:

d913bb7 Use x86_64_general_operand in a bunch more SI mode insn patterns

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3549
TEST= toolchain trybots
R=khim@chromium.org

Review URL: https://codereview.chromium.org/20836003

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@11869 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

Lind-Project/native_client,Lind-Project/native_client,Lind-Project/native_client,Lind-Project/native_client,Lind-Project/native_client,Lind-Project/native_client