Remove packages that use the apps/ structure

They cannot be used as dependencies directly.

index/antidote.mk

@@ -1,7 +0,0 @@
-PACKAGES += antidote
-pkg_antidote_name = antidote
-pkg_antidote_description = Large-scale computation without synchronisation
-pkg_antidote_homepage = https://syncfree.lip6.fr/
-pkg_antidote_fetch = git
-pkg_antidote_repo = https://github.com/SyncFree/antidote
-pkg_antidote_commit = master

index/rebar.mk

@@ -1,7 +0,0 @@
-PACKAGES += rebar
-pkg_rebar_name = rebar
-pkg_rebar_description = Erlang build tool that makes it easy to compile and test Erlang applications, port drivers and releases.
-pkg_rebar_homepage = http://www.rebar3.org
-pkg_rebar_fetch = git
-pkg_rebar_repo = https://github.com/erlang/rebar3
-pkg_rebar_commit = main