Add Android-specific targets to makefiles

We need to do a special passage to create a fat AAR in Android.

Having a target in the makefile to do so would be useful.

added Android Doing labels

assigned to @pierov

mentioned in merge request !360 (merged)

marked this issue as related to tor-browser-build#40609 (closed)

added Backport label

marked this issue as related to tor-browser-build#40608 (closed)

removed the relation with tor-browser-build#40608 (closed)

removed Backport label

closed

marked this issue as related to tor-browser-build#40609 (closed)

removed Doing label