Add missing ext/libxml dependency to ext/soap (php#14285)

This adds the libxml extension to required dependencies for ext/soap
during the configuration phase (PHP_ADD_EXTENSION_DEP) and the runtime
(ZEND_MOD_REQUIRED).

Author: petk

ext/soap/config.m4

@@ -4,14 +4,10 @@ PHP_ARG_ENABLE([soap],
     [Enable SOAP support])])
 
 if test "$PHP_SOAP" != "no"; then
-
-  if test "$PHP_LIBXML" = "no"; then
-    AC_MSG_ERROR([SOAP extension requires LIBXML extension, add --with-libxml])
-  fi
-
   PHP_SETUP_LIBXML(SOAP_SHARED_LIBADD, [
     AC_DEFINE(HAVE_SOAP,1,[ ])
     PHP_NEW_EXTENSION(soap, soap.c php_encoding.c php_http.c php_packet_soap.c php_schema.c php_sdl.c php_xml.c, $ext_shared,, -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1)
     PHP_SUBST(SOAP_SHARED_LIBADD)
   ])
+  PHP_ADD_EXTENSION_DEP(soap, libxml)
 fi

ext/soap/soap.c

@@ -297,6 +297,7 @@ PHP_MINFO_FUNCTION(soap);
 
 static const zend_module_dep soap_deps[] = {
 	ZEND_MOD_REQUIRED("date")
+	ZEND_MOD_REQUIRED("libxml")
 	ZEND_MOD_END
 };