Silence -Werror=unused-parameter

Cast away remaining issues so that new ones don't get lost in the noise.

Change-Id: Iacd6999b0686ce80f9835730d68db6382690fa92
diff --git a/vp8/vp8_cx_iface.c b/vp8/vp8_cx_iface.c
index 3426f59..f81f078 100644
--- a/vp8/vp8_cx_iface.c
+++ b/vp8/vp8_cx_iface.c
@@ -384,6 +384,8 @@
         oxcf->mr_down_sampling_factor.den = mr_cfg->mr_down_sampling_factor.den;
         oxcf->mr_low_res_mode_info        = mr_cfg->mr_low_res_mode_info;
     }
+#else
+    (void)mr_cfg;
 #endif
 
     oxcf->cpu_used               = vp8_cfg.cpu_used;
@@ -628,6 +630,9 @@
         *mem_loc = (void *)shared_mem_loc;
         res = VPX_CODEC_OK;
     }
+#else
+    (void)cfg;
+    (void)mem_loc;
 #endif
     return res;
 }