weston-ini-conf: (re)move Weston remoting support

weston-ini-conf: (re)move Weston remoting support

Remove the support for generating configuration for the Weston
remoting feature based on the weston-remoting DISTRO_FEATURE
from our weston-ini-conf recipe and bbappend.  Handling this has
been moved from meta-agl-core to meta-agl-demo.  As well, the
agl-weston-remoting setup feature dependency on agl-demo has
been removed as it is no longer required.

Bug-AGL: SPEC-5138

Change-Id: I5a5e58dd9097e940d3925bf60ce4e1283d6529b9
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/29902
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
Tested-by: Jenkins Job builder account
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>