boot/barebox-aux: store downloads in same dir as bare barebox

barebox and barebox-aux are really the same package, from the same URL
and the same version. They deserve being stored in the same directory.

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Tested-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit ca7fa117b168e0de81dda35c8cabb615c352a0e9)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

boot/barebox/barebox.mk

@@ -31,6 +31,8 @@ $(1)_SOURCE = barebox-$$($(1)_VERSION).tar.bz2
 $(1)_SITE = https://www.barebox.org/download
 endif
 
+$(1)_DL_SUBDIR = barebox
+
 $(1)_DEPENDENCIES = host-lzop
 $(1)_LICENSE = GPL-2.0 with exceptions
 $(1)_LICENSE_FILES = COPYING