Patch by Andrew C. Morrow: shims to work around macroized getc and putc on...

Patch by Andrew C. Morrow:  shims to work around macroized getc and putc on linux.  On my eglibc 2.13 based Debian system 'getc' is a macro defined in
/usr/include/stdio.h. This decision to make it a macro doesn't seem to
be guarded by any feature test macro as far as I can see.

llvm-svn: 160799