package/pure-ftpd: add optional support for linux-pam

Signed-off-by: Artem Panfilov <apanfilov@spectracom.com>
[Thomas: add explicit --without-pam when linux-pam is not enabled.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/pure-ftpd/pure-ftpd.mk

@@ -57,4 +57,11 @@ ifeq ($(BR2_PACKAGE_PURE_FTPD_UPLOADSCRIPT),y)
 PURE_FTPD_CONF_OPTS += --with-uploadscript
 endif
 
+ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
+PURE_FTPD_CONF_OPTS += --with-pam
+PURE_FTPD_DEPENDENCIES += linux-pam
+else
+PURE_FTPD_CONF_OPTS += --without-pam
+endif
+
 $(eval $(autotools-package))