[Aarch64] Fix vec_perm cost for thunderx2t99

Here is the one-liner that fixes the incorrect
vec_perm cost for thunderx2t99 chip.
With the patch applied 526.blender of CPU2017
gets ~5% improvement with no measurable changes
for other benchmarks.

2019-11-05  Anton Youdkevitch  <anton.youdkevitch@bell-sw.com>

	* config/aarch64/aarch64.c (thunderx2t99_vector_cost):
	Change vec_perm field to 10.

From-SVN: r277826

gcc/ChangeLog

+2019-11-05  Anton Youdkevitch  <anton.youdkevitch@bell-sw.com>
+
+	* config/aarch64/aarch64.c (thunderx2t99_vector_cost):
+	Change vec_perm field to 10.
+
 2019-11-05  Arnaud Charlet  <charlet@adacore.com>
 
 	* doc/install.texi: Further fix syntax for html generation.

gcc/config/aarch64/aarch64.c

@@ -585,7 +585,7 @@ static const struct cpu_vector_cost thunderx2t99_vector_cost =
   1, /* scalar_store_cost  */
   5, /* vec_int_stmt_cost  */
   6, /* vec_fp_stmt_cost  */
-  3, /* vec_permute_cost  */
+  10, /* vec_permute_cost  */
   6, /* vec_to_scalar_cost  */
   5, /* scalar_to_vec_cost  */
   8, /* vec_align_load_cost  */