[PATCH all drivers] config: set more appropriate default drivers location

[Gaetan Nadon]

The current value is based on $lib which is based on the driver package
$prefix. The driver object code will be installed in the correct xserver location
only if both the driver package and the xserver package have the same prefix.

This patch obtains the drivers object code location from the installed xserver
package through the xorg-server.pc file. The server default location for drivers
object code is based on its own $lib but this may have been changed at configuration
time (using with-module-dir). In any case, the resulting net location is returned.

Signed-off-by: Gaetan Nadon <memsize at videotron.ca>
---
 configure.ac |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index c1fae22..c3f33a2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -55,9 +55,9 @@ AH_TOP([#include "xorg-server.h"])
 
 AC_ARG_WITH(xorg-module-dir,
             AC_HELP_STRING([--with-xorg-module-dir=DIR],
-                           [Default xorg module directory [[default=$libdir/xorg/modules]]]),
+                           [Default xorg module directory [[default=$moduledir/xorg/modules]]]),
             [moduledir="$withval"],
-            [moduledir="$libdir/xorg/modules"])
+            [moduledir=`$PKG_CONFIG --variable=moduledir xorg-server`])
 
 AC_ARG_ENABLE(dri, AC_HELP_STRING([--disable-dri],
                                   [Disable DRI support [[default=auto]]]),
-- 
1.6.0.4

My assumption is that the drivers can only be loaded if they are located 
in the running server xorg/modules/drivers directory that it knows 
about at configuration time. If that is correct, the only value that
with-xorg-module-dir can be given is the value that the server returns
through the xorg-server .pc file.

After searching in 2005 archives, I found out some distro did not install
our .pc files or did not install the pkg-config package. Is it still the case?
Would all of our build not fail?
http://lists.x.org/archives/xorg/2006-November/019654.html

It's the first I hear about the pkg-config method not being reliable.