Add --include-cfi compiler option.

Decouple generation of CFI from the rest of debug symbols.
This makes it possible to generate oat with CFI but without
the rest of debug symbols.

This is in line with intention of the .eh_frame section.
The section does not have the .debug_ prefix because it
is considered somewhat different to the rest of debug symbols.

Change-Id: I32816ecd4f30ac4e0dc69d69a4993e349c737f96