dev-perl/Alien-SDL: -r bump for EAPI7

dev-perl/Alien-SDL: -r bump for EAPI7

Also has to fix bug #719074 as EAPI7-ification adds .packlist to
the install, which breaks subsequent reinstalls due to misguided "nuke
existing share dir" logic targeted at CPAN.

And although this issue is fixed for -r1, attempts to downgrade to -r0
will rexperience this bug, even though -r0 didn't typically have the
problem on self-reinstallation ... due to not shipping the .packlist
due to EAPI < 6

A true downgrade requires running some kind of emerge -C operation
to remove the sharedirs, before installing the older version.

Subsequently, this issue can *only* be considered fixed once -r0 is
removed.

Bug: https://bugs.gentoo.org/719074
Package-Manager: Portage-2.3.97, Repoman-2.3.22
Signed-off-by: Kent Fredric <kentnl@gentoo.org>