libubox: Lua binding needs mmu and fix coding style

Fixes
http://autobuild.buildroot.net/results/4e1/4e112e4463fef7ad8757259b222fab10fbd09d0d/

The Lua binding option of libubox uses fork() so it needs the MMU.

By the way, correction of coding style as stated in the buildroot
manual.

Signed-off-by: Hadrien Boutteville <hadrien.boutteville@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/libubox/libubox.mk

@@ -10,12 +10,14 @@ LIBUBOX_LICENSE = LGPLv2.1, GPLv2, BSD-3c, MIT
 LIBUBOX_INSTALL_STAGING = YES
 LIBUBOX_DEPENDENCIES = host-pkgconf $(if $(BR2_PACKAGE_JSON_C),json-c)
 
+ifeq ($(BR2_USE_MMU),y) # fork()
 ifeq ($(BR2_PACKAGE_LUA_5_1),y)
-	LIBUBOX_DEPENDENCIES += lua
-	LIBUBOX_CONF_OPT += -DLUAPATH=$(STAGING_DIR)/usr/lib/lua/5.1 \
-		-DLUA_CFLAGS=-I$(STAGING_DIR)/usr/include
+LIBUBOX_DEPENDENCIES += lua
+LIBUBOX_CONF_OPT += -DLUAPATH=$(STAGING_DIR)/usr/lib/lua/5.1 \
+	-DLUA_CFLAGS=-I$(STAGING_DIR)/usr/include
 else
-	LIBUBOX_CONF_OPT += -DBUILD_LUA:BOOL=OFF
+LIBUBOX_CONF_OPT += -DBUILD_LUA:BOOL=OFF
 endif
+endif # MMU
 
 $(eval $(cmake-package))