apt wasn't building on modern libc/compiler combinations due to missing
header includes.
The libcpp version was also being hardcoded, this patch generates it
dynamically to work on different host systems which no longer have
this.
(From OE-Core rev: ca8237ee51053d70b5e7579c224a824db2be76b2)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Richard Purdie