package/samba4: remove trailing space in samba4.mk

This fixes the following warning from `make check-package`:
    package/samba4/samba4.mk:34: line contains trailing whitespace

Signed-off-by: Titouan Christophe <titouan.christophe@railnova.eu>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/samba4/samba4.mk

@@ -31,7 +31,7 @@ SAMBA4_PYTHON = \
 	PYTHON_CONFIG="$(STAGING_DIR)/usr/bin/python3-config"
 SAMBA4_DEPENDENCIES += host-python3 python3
 else
-SAMBA4_PYTHON = PYTHON="$(HOST_DIR)/bin/python2" 
+SAMBA4_PYTHON = PYTHON="$(HOST_DIR)/bin/python2"
 SAMBA4_DEPENDENCIES += host-python
 SAMBA4_CONF_OPTS += --disable-python
 endif