Fix Windows dump_syms x64 linking

The dia_sdk GYP target points at the x86 diaguids.lib, it needs to
point at the x64 one for x64 builds.
R=mark at https://breakpad.appspot.com/9784002/

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1431 4c0a9323-5329-0410-9bdc-e9ce6186880e
1 file changed