pcr: Add android-tools 31.0.2 for armv7h
    
    The PKGBUILD was taken from the Arch Linux community repository
    which is at https://github.com/archlinux/svntogit-community as
    the old URL (git://git.archlinux.org/svntogit/community.git) isn't
    up to date and according to #archlinux, the migration to gitlab
    isn't complete yet.
    
    Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>