Fix ctype_base::xdigit for Android.

Android's ctype implementation comes from openbsd, which for some reason
doesn't consider numbers to be hex digits.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@213785 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed