util: Move ralloc to a new src/util directory.

For a long time, we've wanted a place to put utility code which isn't
directly tied to Mesa or Gallium internals.  This patch creates a new
src/util directory for exactly that purpose, and builds the contents as
libmesautil.la.

ralloc seemed like a good first candidate.  These days, it's directly
used by mesa/main, i965, i915, and r300g, so keeping it in src/glsl
didn't make much sense.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>

v2 (Jason Ekstrand): More realloc uses and some scons fixes

Signed-off-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
diff --git a/configure.ac b/configure.ac
index 3e56508..b2b61c7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2279,7 +2279,9 @@
 		src/mesa/drivers/osmesa/osmesa.pc
 		src/mesa/drivers/x11/Makefile
 		src/mesa/main/tests/Makefile
-		src/mesa/main/tests/hash_table/Makefile])
+		src/mesa/main/tests/hash_table/Makefile
+		src/util/Makefile
+		src/util/tests/Makefile])
 
 dnl Sort the dirs alphabetically
 GALLIUM_TARGET_DIRS=`echo $GALLIUM_TARGET_DIRS|tr " " "\n"|sort -u|tr "\n" " "`