[Mesa-dev] Automake/subdir-object/makefile.sources cleanups

[Emil Velikov]

Hello list,

Here is a follow up patchset to the Makefile.sources, targeting the following
* move source files lists to Makefile.sources (symmetry and reuse accross
build systems)
* creates symlinks and enables subdir-objects (preparation as the option
defaults to enabled with Automake 2.0)
* consolidates common flags into Automake.inc

Patch 1: Renames a few variables to silence automake/autoconf 'missing
program or library' warning.

Patch 2,3: Remove FEATURE_* leftovers. (scons/Android)

Patch 4: Moves/compacts all three freedreno sets of Makefile.{am,sources}
into one. (patch originaly from Johannes Obermayr)

Patch 5: Moves the dri/common SConscript to be beside the Automake/Android
one. The patch is a RFC, as my current scons fu is a bit short.

Patch 6-13: Move source file lists to Makefile.sources, and enable
subdir-objects for those directories.

Patch 14-22: Adds symlinks in order to get subdir-objects working properly.

Patch 23-37: Compacts various gallium flags into Automake.inc.
* VISIBILITY_CFLAGS has been added to all dri, xorg, vdpau, xvmc targets.

Some of the above may become obsolete depending when/if Marek's patches
wrt removing various xorg, xvmc, vdpau targets gets merged.

The whole branch subdir-objects-v2 can be found over at
https://github.com/evelikov/Mesa.git

I've tested dri/vdpau on swrast/nouveau and I did not see any problems,
I would appreciate if more people can give it a try.
Note: I'm still in process of setting up an Android build, so only
automake/scons has been tested.

Any comments and review would be greatly appreciated.

Cheers
Emil