bpo-39573: Finish converting to new Py_IS_TYPE() macro (GH-18601)

diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index e0a666f..3d99f11 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -8484,7 +8484,7 @@
     char *outstart;
     Py_ssize_t outsize = PyBytes_GET_SIZE(*outobj);
 
-    if (Py_TYPE(mapping) == &EncodingMapType) {
+    if (Py_IS_TYPE(mapping, &EncodingMapType)) {
         int res = encoding_map_lookup(c, mapping);
         Py_ssize_t requiredsize = *outpos+1;
         if (res == -1)
@@ -8563,7 +8563,7 @@
     /* find all unencodable characters */
     while (collendpos < size) {
         PyObject *rep;
-        if (Py_TYPE(mapping) == &EncodingMapType) {
+        if (Py_IS_TYPE(mapping, &EncodingMapType)) {
             ch = PyUnicode_READ_CHAR(unicode, collendpos);
             val = encoding_map_lookup(ch, mapping);
             if (val != -1)