[libcxxabi] Disable calls to fprintf for baremetal targets.

We've been having issues with using libcxxabi and libunwind for baremetal
targets because fprintf is dependent on io functions, this patch disables calls
to fprintf when building for baremetal in release mode.

Differential Revision: https://reviews.llvm.org/D30339



git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@296136 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed