glsl: Add lower_vector.cpp to SConscript.
diff --git a/src/glsl/SConscript b/src/glsl/SConscript
index f708635..fd22f66 100644
--- a/src/glsl/SConscript
+++ b/src/glsl/SConscript
@@ -57,6 +57,7 @@
     'lower_variable_index_to_cond_assign.cpp',
     'lower_vec_index_to_cond_assign.cpp',
     'lower_vec_index_to_swizzle.cpp',
+    'lower_vector.cpp',
     'opt_algebraic.cpp',
     'opt_constant_folding.cpp',
     'opt_constant_propagation.cpp',