The last time configure was run, it was run on a system that
did not enable -std=gnu11 by default, which meant that the
restrict qualifier would not be recognized on certain platforms.
This regenerates the configure files from running bootstrap.sh,
so that these should be recognized on all supported platforms.

Resolves: #586
(cherry picked from commit 54b804fc3bba03b6d3ae0446bf2a1b01aec08574)