Remove disable_diagonal_intra from cfg_options_t

Remove the disable_diagonal_intra field from the cfg_options_t struct.
The cfg_options_t struct is a public type and is embedded in the
aom_codec_enc_cfg_t struct, so adding a field to the cfg_options_t
struct breaks binary compatibility with libaom v3.0.0.

BUG=aomedia:3033

Change-Id: Id5c4b47e7a2395220922cdd4c42aa1694b42ebcb
(cherry picked from commit faa02f0daf6bc11bf480ada1987088416132f93c)
diff --git a/aom/aom_encoder.h b/aom/aom_encoder.h
index beac764..b2926e1 100644
--- a/aom/aom_encoder.h
+++ b/aom/aom_encoder.h
@@ -293,10 +293,6 @@
    *
    */
   unsigned int disable_smooth_intra;
-  /*!\brief disable D45 to D203 intra modes
-   *
-   */
-  unsigned int disable_diagonal_intra;
   /*!\brief disable filter intra
    *
    */
diff --git a/apps/aomenc.c b/apps/aomenc.c
index 11035bf..5eb8c82 100644
--- a/apps/aomenc.c
+++ b/apps/aomenc.c
@@ -1301,7 +1301,6 @@
     SHOW_PARAMS(disable_intrabc);
     SHOW_PARAMS(disable_cfl);
     SHOW_PARAMS(disable_smooth_intra);
-    SHOW_PARAMS(disable_diagonal_intra);
     SHOW_PARAMS(disable_filter_intra);
     SHOW_PARAMS(disable_dual_filter);
     SHOW_PARAMS(disable_intra_angle_delta);
diff --git a/av1/av1_cx_iface.c b/av1/av1_cx_iface.c
index 13456b2..419af27 100644
--- a/av1/av1_cx_iface.c
+++ b/av1/av1_cx_iface.c
@@ -680,7 +680,6 @@
   extra_cfg->enable_smooth_intra = (cfg->disable_smooth_intra == 0);
   extra_cfg->enable_paeth_intra = (cfg->disable_paeth_intra == 0);
   extra_cfg->enable_cfl_intra = (cfg->disable_cfl == 0);
-  extra_cfg->enable_diagonal_intra = (cfg->disable_diagonal_intra == 0);
   extra_cfg->enable_obmc = (cfg->disable_obmc == 0);
   extra_cfg->enable_palette = (cfg->disable_palette == 0);
   extra_cfg->enable_intrabc = (cfg->disable_intrabc == 0);
@@ -3426,7 +3425,7 @@
       0,                       // use_fixed_qp_offsets
       { -1, -1, -1, -1, -1 },  // fixed_qp_offsets
       { 0, 128, 128, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
+        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
   },
   {
       // NOLINT
@@ -3496,7 +3495,7 @@
       0,                       // use_fixed_qp_offsets
       { -1, -1, -1, -1, -1 },  // fixed_qp_offsets
       { 0, 128, 128, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
+        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
   },
   {
       // NOLINT
@@ -3566,7 +3565,7 @@
       0,                       // use_fixed_qp_offsets
       { -1, -1, -1, -1, -1 },  // fixed_qp_offsets
       { 0, 128, 128, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
+        0, 0,   0,   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },  // cfg
   },
 };
 
diff --git a/common/args.c b/common/args.c
index 64d6e03..ed62294 100644
--- a/common/args.c
+++ b/common/args.c
@@ -92,7 +92,6 @@
     GET_PARAMS(disable_intrabc);
     GET_PARAMS(disable_cfl);
     GET_PARAMS(disable_smooth_intra);
-    GET_PARAMS(disable_diagonal_intra);
     GET_PARAMS(disable_filter_intra);
     GET_PARAMS(disable_dual_filter);
     GET_PARAMS(disable_intra_angle_delta);