* gc.c (gc_prof_set_heap_info): fix compile error when
  GC_PROFILE_MORE_DETAIL != 0.
  the patch is provided by ko1 (Koichi Sasada).


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@43429 b2dd03c8-39d4-4d8f-98ff-823fe69b080e