net-libs/webkit-gtk: security bump to 2.24.1, drop JIT control

net-libs/webkit-gtk: security bump to 2.24.1, drop JIT control

JIT manual control is getting complicated for limited benefits, which
mostly involve oneself shooting in the foot. Let upstream build system
figure out whether it should do JIT or not and don't get in the way.
May be revisited based on any fallout and relevant bug reports after
discussions on such reports convince it's needed.

Bug: https://bugs.gentoo.org/683234
Bug: https://bugs.gentoo.org/680580
Bug: https://bugs.gentoo.org/680464
Package-Manager: Portage-2.3.52, Repoman-2.3.12
Signed-off-by: Mart Raudsepp <leio@gentoo.org>