connman: Remove obsolete configurations from EXTRA_OECONF

--enable-threads and --enable-fake are obsolete, unrecognized options
for connman now.

Signed-off-by: Muhammad Shakeel <muhammad_shakeel@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
connman: Upgrade to v1.18

This release contains a few important bugfixes in addition
to a few new features.

Signed-off-by: Muhammad Shakeel <muhammad_shakeel@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
kernel.bbclass: unset LDFLAGS when run devshell in kernel recipe

When user runs devshell in kernel recipe and compiles kernel,
this will fail by unrecognized option of LD.

----
$ make
...
arm-poky-linux-gnueabi-ld: unrecognized option '-Wl,-O1'
arm-poky-linux-gnueabi-ld: use the --help option for usage information
----

This set to empty LDFLAGS when user runs the devshell, and solve this problem.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>