Obviously attempts to provide space for a known configuration-
dependent stack hog. The hog went away when finish_sects()'s arrays
became dynamically allocated in 4.2.0.
Adjusting for that by dropping the extra term might well do (I observe
only a few KiB of stack used on my system). But let's set it to 512
KiB instead to be on the safe side.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>