src/types.c: Fix up the table-of-contents comments.

src/types.c: Fix up the table-of-contents comments.

Cheesy but useful sed(1) rune:

	sed -n '
	  /order of sections/,/\*\//d
	  /^ \* _/s///p
	  /^static \+[a-z0-9_]\+ \+\**\([0-9a-z_]\+\).*$/s//  \1/p'

Signed-off-by: Mark Wooding <mdw@distorted.org.uk>