[Buildroot] [PATCH] core/pkg-infra: host variant inherits DL_SUBDIR

[Yann E. MORIN]

We have no clear separation between variables that should be
automatically inherited by the host variant, from the target
variant, and those variables that should not be inherited.

However, it clearly makes sense that the host variant does inherit
all the download variables, of which the sub-directory.

Notes: currently, only three packages define HOST_FOO_DL_SUBDIR,
but they all are host-only packages anyway, so needs not be fixed:
  - gcc-initial
  - gcc-final
  - python3-setuptools

Signed-off-by: Yann E. MORIN <yann.morin.1998 at free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
Cc: Peter Korsgaard <peter at korsgaard.com>
Cc: Maxime Hadjinlian <maxime.hadjinlian at gmail.com>
---
 package/pkg-generic.mk | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index 67782138b4..5c7c039390 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -466,6 +466,12 @@ ifdef $(3)_OVERRIDE_SRCDIR
   $(2)_OVERRIDE_SRCDIR ?= $$($(3)_OVERRIDE_SRCDIR)
 endif
 
+ifndef $(2)_DL_SUBDIR
+ ifdef $(3)_DL_SUBDIR
+  $(2)_DL_SUBDIR = $$($(3)_DL_SUBDIR)
+ endif
+endif
+
 $(2)_BASENAME	= $$(if $$($(2)_VERSION),$(1)-$$($(2)_VERSION),$(1))
 $(2)_BASENAME_RAW = $$(if $$($(2)_VERSION),$$($(2)_RAWNAME)-$$($(2)_VERSION),$$($(2)_RAWNAME))
 $(2)_DL_SUBDIR ?= $$($(2)_RAWNAME)
-- 
2.14.1