clean up code formatting

for future reference, this was done with:
find . -name '*.[ch]' -exec indent -bad -bap -br -ce -cdw -cli2 -npcs -nss \
-nbs -saf -sai -saw -nprs -nsob -npsl -bli1 -brs -brf -ppi3 -i3 '{}' \;

results are not perfect, in particular it overzealously adds blank lines in
definition blocks, but it's a big improvement and reasonable approximation of
JED "C-mode with cuddling" style