Move context and coroutine

Yocto upstream moved context and coroutine directly into BOOST_LIBS,
which means that they're not added back for our arm variant.

https://github.com/lgirdk/poky/commit/624262541605c476f5a0bd415b08d00379c15b00



This causes our build to fail with "cannot find -lboost_coroutine"
errors.  This should resolve it.

Tested:
Fixing CI break.  No functional testing done.

(From meta-phosphor rev: 6be1787fdc13405fa9daa6755c28534bbcaa7458)

Signed-off-by: Ed Tanous <ed@tanous.net>
Change-Id: I60d7bb8ea25a08bfdb399f8addfaf560fd7a7b7c
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>