Solve two ssl issues; always install both ab.exe and abs.exe

because it's easier to move around ab.exe when that's all
someone needs (and this is precisely how the binary installer
works, too), and also kindly ignore missing openssl tree files
because TIMTOWTDI (although this one is preferred :)

Backport: r606382, r606383

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@606384 13f79535-47bb-0310-9956-ffa450edef68