builtins: add AEABI div0 functions

Add the missing AEABI functions that are part of the base platform ABI
specification.  The provided implementation does the bare minimum to avoid
requiring libc headers.  This permits the use of compiler-rt on bare-metal
environments which conform to EABI.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@217322 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 2b2f4db4cd6a28a0259ba7298f8599c07fb4ec59)
2 files changed