Disable testcases 12 and 15-22 on FreeBSD

Submitted by: pho


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273948 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Add new atf_tc_expect_fail to fflush_err; this is a new (within the past couple months) bug


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273949 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Skip :fopen_regular on !NetBSD because it's a NetBSD specific test

Submitted by: pho


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273950 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Expect :sscanf_whitespace to fail on !NetBSD OSes

Submitted by: pho


git-svn-id: svn+ssh://svn.freebsd.org/base/head@273951 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f