libpam: add ptest cases back

It removes the installation of ptest cases when upgrade libpam to 1.7.0.
Add them back to make ptest work. And 2 more cases in libpam 1.7.0.

(From OE-Core rev: ba8266267b4a89285bba0fceeaa1507957d318fb)

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-extended/pam/libpam_1.7.0.bb

@@ -142,6 +142,12 @@ do_install:append() {
 	fi
 }
 
+do_install_ptest() {
+    mkdir -p ${D}${PTEST_PATH}/tests
+    find ${B}/tests -maxdepth 1 -type f -exec cp {} ${D}${PTEST_PATH}/tests \;
+    install -m 0644 ${S}/tests/confdir ${D}${PTEST_PATH}/tests
+}
+
 pkg_postinst:${PN}() {
          if [ -z "$D" ] && [ -e /etc/init.d/populate-volatile.sh ] ; then
                  /etc/init.d/populate-volatile.sh update