Use switch instead of if, and handle all enum values.
Use switch instead of if, and handle all enum values.

This patch also handles errors other than no_more_files error. They were silently
ignored.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@192415 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld