scons: Define PACKAGE_VERSION/BUGREPORT globally.

Fixes the scons build.
diff --git a/SConstruct b/SConstruct
index 4a3fef0..1807ff8 100644
--- a/SConstruct
+++ b/SConstruct
@@ -69,6 +69,11 @@
 #######################################################################
 # Environment setup
 
+env.Append(CPPDEFINES = [
+    ('PACKAGE_VERSION', '\\"9.2-devel\\"'),
+    ('PACKAGE_BUGREPORT', '\\"https://bugs.freedesktop.org/enter_bug.cgi?product=Mesa\\"'),
+])
+
 # Includes
 env.Prepend(CPPPATH = [
 	'#/include',