Renamings for OBMC experiment

To get ready for pulling AV1 to nextgenv2
Replace the experimental flag by MOTION_VAR. Rename major variables.

Change-Id: If6cf4f37b9319c46d8f90df551cc7295d66ca205
diff --git a/aom_dsp/variance.h b/aom_dsp/variance.h
index b73754f..222fdaf 100644
--- a/aom_dsp/variance.h
+++ b/aom_dsp/variance.h
@@ -68,7 +68,7 @@
     unsigned int *sse);
 #endif  // CONFIG_AV1 && CONFIG_EXT_INTER
 
-#if CONFIG_AV1 && CONFIG_OBMC
+#if CONFIG_AV1 && CONFIG_MOTION_VAR
 typedef unsigned int (*aom_obmc_sad_fn_t)(const uint8_t *pred, int pred_stride,
                                           const int32_t *wsrc,
                                           const int32_t *msk);
@@ -80,7 +80,7 @@
 typedef unsigned int (*aom_obmc_subpixvariance_fn_t)(
     const uint8_t *pred, int pred_stride, int xoffset, int yoffset,
     const int32_t *wsrc, const int32_t *msk, unsigned int *sse);
-#endif  // CONFIG_AV1 && CONFIG_OBMC
+#endif  // CONFIG_AV1 && CONFIG_MOTION_VAR
 
 #if CONFIG_AV1
 typedef struct aom_variance_vtable {
@@ -97,11 +97,11 @@
   aom_masked_variance_fn_t mvf;
   aom_masked_subpixvariance_fn_t msvf;
 #endif  // CONFIG_EXT_INTER
-#if CONFIG_OBMC
+#if CONFIG_MOTION_VAR
   aom_obmc_sad_fn_t osdf;
   aom_obmc_variance_fn_t ovf;
   aom_obmc_subpixvariance_fn_t osvf;
-#endif  // CONFIG_OBMC
+#endif  // CONFIG_MOTION_VAR
 } aom_variance_fn_ptr_t;
 #endif  // CONFIG_AV1