r600g/sb: Initialize shader::dce_flags.

Fixes "Uninitialized scalar field" defect reported by Coverity.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Vadim Girlin <vadimgirlin@gmail.com>

src/gallium/drivers/r600/sb/sb_shader.cpp

@@ -39,7 +39,8 @@ shader::shader(sb_context &sctx, shader_target t, unsigned id)
   coal(*this), bbs(),
   target(t), vt(ex), ex(*this), root(),
   compute_interferences(),
-  has_alu_predication(), uses_gradients(), safe_math(), ngpr(), nstack() {}
+  has_alu_predication(),
+  uses_gradients(), safe_math(), ngpr(), nstack(), dce_flags() {}
 
 bool shader::assign_slot(alu_node* n, alu_node *slots[5]) {