Update nss tests to new skeleton

* bug17079.c: Update to new test harness.
* test-digits-dots.c: Likewise.
* test-netdb.c: Likewise.
* tst-field.c: Likewise.
* tst-nss-getpwent.c: Likewise.
* tst-nss-static.c: Likewise.
* tst-nss-test1.c: Likewise.
* tst-nss-test2.c: Likewise.
* tst-nss-test3.c: Likewise.
* tst-nss-test4.c: Likewise.
* tst-nss-test5.c: Likewise.