jansson: upgraded package to upstream

Upgraded dev-libs/jansson to version 2.10 on amd64, arm, x86

BUG=b:77218095
TEST=Verify `for i in {amd64,arm,x86}-generic; do
emerge-$i dev-libs/jansson; done` succeeds.

Change-Id: I433c911e1f84e121590afe311354610d2879c6e8
Reviewed-on: https://chromium-review.googlesource.com/1006048
Commit-Ready: Joshua Emele <jemele@google.com>
Tested-by: Joshua Emele <jemele@google.com>
Reviewed-by: Ben Chan <benchan@chromium.org>
4 files changed