bpo-35582: Argument Clinic: Optimize the "all boring objects" case. (GH-11520)

Use _PyArg_CheckPositional() and inlined code instead of
PyArg_UnpackTuple() and _PyArg_UnpackStack() if all parameters
are positional and use the "object" converter.
diff --git a/Objects/clinic/bytesobject.c.h b/Objects/clinic/bytesobject.c.h
index 4e754d9..d75bbf1 100644
--- a/Objects/clinic/bytesobject.c.h
+++ b/Objects/clinic/bytesobject.c.h
@@ -203,11 +203,14 @@
     PyObject *return_value = NULL;
     PyObject *bytes = Py_None;
 
-    if (!_PyArg_UnpackStack(args, nargs, "strip",
-        0, 1,
-        &bytes)) {
+    if (!_PyArg_CheckPositional("strip", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    bytes = args[0];
+skip_optional:
     return_value = bytes_strip_impl(self, bytes);
 
 exit:
@@ -234,11 +237,14 @@
     PyObject *return_value = NULL;
     PyObject *bytes = Py_None;
 
-    if (!_PyArg_UnpackStack(args, nargs, "lstrip",
-        0, 1,
-        &bytes)) {
+    if (!_PyArg_CheckPositional("lstrip", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    bytes = args[0];
+skip_optional:
     return_value = bytes_lstrip_impl(self, bytes);
 
 exit:
@@ -265,11 +271,14 @@
     PyObject *return_value = NULL;
     PyObject *bytes = Py_None;
 
-    if (!_PyArg_UnpackStack(args, nargs, "rstrip",
-        0, 1,
-        &bytes)) {
+    if (!_PyArg_CheckPositional("rstrip", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    bytes = args[0];
+skip_optional:
     return_value = bytes_rstrip_impl(self, bytes);
 
 exit:
@@ -559,4 +568,4 @@
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=810c8dfc72520ca4 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=c6621bda84e63e51 input=a9049054013a1b77]*/