package/samba4: fix build without python3

python3 is mandatory since version 4.11 and
https://gitlab.com/samba-team/samba/commit/63d20d7822ead1626f7cb41fdbae6c9300893314

The only way to build samba4 without python3 is to disable python
bindings through --disable-python option

Fixes:
 - http://autobuild.buildroot.org/results/c4bb3d41fa07e38f0360a563bdcb4a368740cfe5

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/samba4/samba4.mk

@@ -31,10 +31,9 @@ SAMBA4_PYTHON = \
 	PYTHON_CONFIG="$(STAGING_DIR)/usr/bin/python3-config"
 SAMBA4_DEPENDENCIES += host-python3 python3
 else
-SAMBA4_PYTHON = \
-	PYTHON="$(HOST_DIR)/bin/python2" \
-	PYTHON_CONFIG="$(STAGING_DIR)/usr/bin/python-config"
-SAMBA4_DEPENDENCIES += host-python python
+SAMBA4_PYTHON = PYTHON="$(HOST_DIR)/bin/python2" 
+SAMBA4_DEPENDENCIES += host-python
+SAMBA4_CONF_OPTS += --disable-python
 endif
 
 ifeq ($(BR2_PACKAGE_LIBTIRPC),y)