core/pkg-kernel-config: ensure linux supports modules (branch yem/kernel-module)

Hello All!

This series fixes two standing issues with the way we handle packages that build kernel modules:

- first, the current check is broken, because $(LINUX_DIR) should be double-$ed, as it is used in a macro from an infra,

- second, it is currently possible to (try to) build such packages without the kernel config havong CONFIG_MODULES set.

NOTE: The tree is currently *broken* for any package that uses the kernel-module infra. The release is broken, too.

So, these three patches fix that:

- introduce a new internal variable to tell the kernel to enable support for modules, LINUX_NEEDS_MODULES, that should be set whenever a package wants to build a kernel modules, and is automatically set by the kernel-module infra,

- the (broken) check is no longer needed so removed,

- a few packages that build kernel modules without using the kernel-module infra are fixed to manually set that variable.

Thanks to Peter for suggesting the solution, and to No? and Jan for their previous attempts that eventually led to this series.

Changes v2 -> v3:
- add reference to the commit bewing reverted (Arnout)
- slight eye-candy, remove trailing colons (Arnout)

Changes v1 -> v2:
- do not force CONFIG_MODULES if requesting package is not enabled (Peter, Jan)
- update commit log that the check was broken anyway
- add 4th patch to slightly improve linux-fusion

Regards,
Yann E. MORIN.

The following changes since commit 91f12b7e7a013e3db639e0fa44ac395ac46442f2:

tar: move package to 'system tools' (2015-09-01 22:28:49 +0200)

are available in the git repository at:

git://git.busybox.net/~ymorin/git/buildroot yem/kernel-module

for you to fetch changes up to 40510fd321964fdd1918ce29a65a68f142bf2c71:

package/linux-fusion: slight simplification (2015-09-03 14:48:34 +0200)

----------------------------------------------------------------
Yann E. MORIN (4):
core/pkg-kernel-module: ensure linux supports modules core/pkg-kernel-module: drop now-useles check for CONFIG_MODULES
packages: ensure linux supports modules even when not using kernel-module package/linux-fusion: slight simplification

 linux/linux.mk                           |  2 ++
 package/linux-fusion/linux-fusion.mk     | 11 ++++++++---
 package/nvidia-driver/nvidia-driver.mk   |  4 ++++
 package/pkg-kernel-module.mk             |  9 +++++----
 package/racehound/racehound.mk           |  6 ++++++
 package/rtai/rtai.mk                     |  6 ++++++
 package/ti-gfx/ti-gfx.mk                 |  7 +++++++
 package/xtables-addons/xtables-addons.mk |  6 ++++++
 8 files changed, 44 insertions(+), 7 deletions(-)

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