Fix DEBUG_NEEDS usage

Change-Id: Ic107c60080e55e1f9092f20fe3bd55e7592ca9fd
diff --git a/libpixelflinger/scanline.cpp b/libpixelflinger/scanline.cpp
index 8fba147..a37b47e 100644
--- a/libpixelflinger/scanline.cpp
+++ b/libpixelflinger/scanline.cpp
@@ -350,7 +350,7 @@
         }
     }
 
-#ifdef DEBUG_NEEDS
+#if DEBUG_NEEDS
     LOGI("Needs: n=0x%08x p=0x%08x t0=0x%08x t1=0x%08x",
          c->state.needs.n, c->state.needs.p,
          c->state.needs.t[0], c->state.needs.t[1]);