tcmalloc: fixes for the windows addr2line wrapper

Fixes a few small format string bugs and makes the windows library
configuration #defines more friendly for chromium builds.

Based on original CL: https://codereview.chromium.org/2730473002

BUG=724399,b:70905156

Change-Id: If54c6cfc5c508744d2ee18f251677b2456acda72
1 file changed