autotools: get the PAM support from master working on linux and freebsd

cde/programs/dtsession/config/Makefile.am

@@ -0,0 +1,23 @@
+MAINTAINERCLEANFILES = Makefile.in
+
+CPP_TARGET = pam.d.dtsession
+
+BUILT_SOURCES = $(CPP_TARGET)
+CLEANFILES = $(CPP_TARGET)
+
+cfgdir = $(CDE_INSTALLATION_TOP)/config
+dist_cfg_DATA = $(CPP_TARGET)
+
+
+if FREEBSD
+PAM_AUTHENTICATION_MODULE = /usr/local/lib/security/pam_pwauth_suid.so
+endif
+
+if NETBSD
+PAM_AUTHENTICATION_MODULE = /usr/pkg/lib/security/pam_pwauth_suid.so
+endif
+
+pam.d.dtsession: pam.d.dtsession.src
+	$(RM) $@
+	$(GENCPP) -P -DXCOMM=# -DPAM_AUTHENTICATION_MODULE=$(PAM_AUTHENTICATION_MODULE) $< > $@
+