package/polkit: support different authentication frameworks

Use pam if available, otherwise use shadow.

Signed-off-by: Adam Duskett <Aduskett@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/polkit/polkit.mk

@@ -13,13 +13,17 @@ POLKIT_INSTALL_STAGING = YES
 
 POLKIT_DEPENDENCIES = libglib2 host-intltool expat spidermonkey
 
-# We could also support --with-authfw=pam
 POLKIT_CONF_OPTS = \
-	--with-authfw=shadow \
 	--with-os-type=unknown \
 	--disable-man-pages \
 	--disable-examples \
 	--disable-libelogind \
 	--disable-libsystemd-login
 
+ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
+POLKIT_CONF_OPTS += --with-authfw=pam
+else
+POLKIT_CONF_OPTS += --with-authfw=shadow
+endif
+
 $(eval $(autotools-package))