LTO: Improve error reporting when adding a cache entry.

Move error handling code next to the code that returns the error,
and change the error message in order to distinguish it from a similar
error message elsewhere in this file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314745 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed