Fix missing check for xmlTextWriterEndElement

xmlTextWriterEndElement returns -1 if the call fails. There was already
a check for retval, but the return value wasn't assigned to retval. The
other caller of xmlTextWriterEndElement is in
xmlwriter_write_element_ns, which does the check correctly.

Closes GH-10324

Signed-off-by: George Peter Banyard <girgias@php.net>

Author: nielsdos

NEWS

@@ -53,6 +53,9 @@ PHP                                                                        NEWS
 - TSRM:
   . Fixed Windows shmget() wrt. IPC_PRIVATE. (Tyson Andre)
 
+- XMLWriter
+  . Fix missing check for xmlTextWriterEndElement (nielsdos)
+
 05 Jan 2023, PHP 8.1.14
 
 - Core:

ext/xmlwriter/php_xmlwriter.c

@@ -449,7 +449,7 @@ PHP_FUNCTION(xmlwriter_write_element)
 			if (retval == -1) {
 				RETURN_FALSE;
 			}
-			xmlTextWriterEndElement(ptr);
+			retval = xmlTextWriterEndElement(ptr);
 			if (retval == -1) {
 				RETURN_FALSE;
 			}