MDEV-13516: encryption.create_or_replace test fails in buildbot with InnoDB assertion failure

fil_crypt_rotate_pages
	If tablespace is marked as stopping stop also page rotation

fil_crypt_flush_space
	If tablespace is marked as stopping do not try to read
	page 0 and write it back.

storage/innobase/fil/fil0crypt.cc

@@ -2019,6 +2019,12 @@ fil_crypt_rotate_pages(
 			continue;
 		}
 
+		/* If space is marked as stopping, stop rotating
+		pages. */
+		if (state->space->is_stopping()) {
+			break;
+		}
+
 		fil_crypt_rotate_page(key_state, state);
 	}
 }
@@ -2067,6 +2073,7 @@ fil_crypt_flush_space(
 		crypt_data->type = CRYPT_SCHEME_UNENCRYPTED;
 	}
 
+	if (!space->is_stopping()) {
 		/* update page 0 */
 		mtr_t mtr;
 		mtr_start(&mtr);
@@ -2081,6 +2088,7 @@ fil_crypt_flush_space(
 		crypt_data->write_page0(frame, &mtr);
 
 		mtr_commit(&mtr);
+	}
 }
 
 /***********************************************************************

storage/xtradb/fil/fil0crypt.cc

@@ -2019,6 +2019,12 @@ fil_crypt_rotate_pages(
 			continue;
 		}
 
+		/* If space is marked as stopping, stop rotating
+		pages. */
+		if (state->space->is_stopping()) {
+			break;
+		}
+
 		fil_crypt_rotate_page(key_state, state);
 	}
 }
@@ -2067,6 +2073,7 @@ fil_crypt_flush_space(
 		crypt_data->type = CRYPT_SCHEME_UNENCRYPTED;
 	}
 
+	if (!space->is_stopping()) {
 		/* update page 0 */
 		mtr_t mtr;
 		mtr_start(&mtr);
@@ -2081,6 +2088,7 @@ fil_crypt_flush_space(
 		crypt_data->write_page0(frame, &mtr);
 
 		mtr_commit(&mtr);
+	}
 }
 
 /***********************************************************************