package/busybox: fix unexpected indent with tabs

Signed-off-by: Adam Duskett <aduskett@codeblue.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/busybox/busybox.mk

@@ -52,7 +52,7 @@ BUSYBOX_MAKE_OPTS = \
 	SKIP_STRIP=y
 
 ifndef BUSYBOX_CONFIG_FILE
-	BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
+BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
 endif
 
 BUSYBOX_KCONFIG_FILE = $(BUSYBOX_CONFIG_FILE)