[asan_symbolize] Fix broken pipe handling for python 2.7
[asan_symbolize] Fix broken pipe handling for python 2.7

I D65322 I added a check for BrokenPipeError. However, python 2.7 doesn't
have BrokenPipeError. To be python 2.7 and 3 compatible we need to catch
IOError instead and check for errno == errno.EPIPE.

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@370025 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt