Upgrade to new gold linker.

It turns out that there is a bug in the gold linker that can mess up
unwind tables under certain circumstances. This bug is fixed in a later
version, so swith to use the new version.

This is the gold linker from the gcc-4.9 prebuilts.

Bug: 20671809

(cherry picked from commit 2cd52f0de65e7a5edac7af089638a8d3a8a0c48d)

Change-Id: I126bc4323a01d5334ee750c35575a515863c32c7
diff --git a/bin/x86_64-linux-android-ld.gold b/bin/x86_64-linux-android-ld.gold
index 4778b05..b9e94bf 100755
--- a/bin/x86_64-linux-android-ld.gold
+++ b/bin/x86_64-linux-android-ld.gold
Binary files differ