package/lxc: fix build without linux-pam

Fix typo added by commit
86deafe8635738c3f9efcbda5b22883504d59129:

make: *** No rule to make target '--disable-pam', needed by '/nvmedata/autobuild/instance-0/output-1/build/lxc-4.0.12/.stamp_configured'.  Stop.

Fixes:
 - http://autobuild.buildroot.org/results/ce1be5a8152f7c9aa0f6e59abff035f97a3fd423

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/lxc/lxc.mk

@@ -55,7 +55,7 @@ ifeq ($(BR2_PACKAGE_LINUX_PAM),y)
 LXC_CONF_OPTS += --enable-pam
 LXC_DEPENDENCIES += linux-pam
 else
-LXC_DEPENDENCIES += --disable-pam
+LXC_CONF_OPTS += --disable-pam
 endif
 
 ifeq ($(BR2_PACKAGE_OPENSSL),y)