Minor FreeBSD compile fix from Ry:

http://codereview.chromium.org/2098019/show
Should fix http://code.google.com/p/v8/issues/detail?id=716


git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4718 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/platform-freebsd.cc

@@ -290,7 +290,7 @@ int OS::StackWalk(Vector<OS::StackFrame> frames) {
 
   int frames_count = backtrace(addresses.start(), frames_size);
 
-  char** symbols = backtrace_symbols(addresses, frames_count);
+  char** symbols = backtrace_symbols(addresses.start(), frames_count);
   if (symbols == NULL) {
     return kStackWalkError;
   }