MDEV-12915 ST_Centroid does not return the same result than MySQL.

        Test fixed for IA64.

mysql-test/t/gis.test

@@ -356,15 +356,15 @@ insert into t1 values ('85984',GeomFromText('MULTIPOLYGON(((-115.006363
 36.248666,-115.263639 36.247466,-115.263839 36.252766,-115.261439
 36.252666,-115.261439 36.247366,-115.247239 36.247066)))'));
 
-# Expected result is 115.31877315203187, but IA64 returns 115.31877315203188
-# due to fused multiply-add instructions.
---replace_result 115.31877315203188 115.31877315203187
+# Expected results are 115.2970604672862 and 36.23335610879993, but IA64 returns
+# slightly different values due to fused multiply-add instructions.
+--replace_result 115.29706047613604 115.2970604672862 36.23335611157958 36.23335610879993
 select object_id, geometrytype(geo), ISSIMPLE(GEO), ASTEXT(centroid(geo)) from
 t1 where object_id=85998;
 
-# Expected result is 36.3310176346905, but IA64 returns 36.3310176346904
+# Expected result is 36.34725218253213, but IA64 returns 36.34725217627852
 # due to fused multiply-add instructions.
---replace_result 36.3310176346904 36.3310176346905 -114.87787186923326 -114.87787186923313 36.33101763469053 36.33101763469059 36.33101763469043 36.33101763469059
+--replace_result 36.34725217627852 36.34725218253213 -114.86854470090232 -114.86854472054372
 select object_id, geometrytype(geo), ISSIMPLE(GEO), ASTEXT(centroid(geo)) from
 t1 where object_id=85984;