isisd,ospf6d,bgpd: Fix GCC 6 warnings on indentation not matching control flow

GCC 6 can now give warnings when the indentation of code does not
align with the scope of prior control flow statement(s).  I.e., where
the code visually suggests one kind of control flow, but in actuality
follows another.

Fix warnings found. They all seem to be simple cases of the indentation being
deceptive, but the existing flow being correct.
5 files changed