Fix #76512: \w no longer includes unicode characters

The migration from PCRE to PCRE2 missed to rename once occurrence of
`PCRE_UCP` to `PCRE2_UCP`.  We fix that.  We also revert the changes to
bug52971.phpt which had been incorrectly made in commit a5bc5ae[1].

[1] <http://git.php.net/?p=php-src.git;a=commit;h=a5bc5aed71f7a15f14f33bb31b8e17bf5f327e2d>

NEWS

@@ -6,6 +6,9 @@ PHP                                                                        NEWS
   . Fixed bug #73342 (Vulnerability in php-fpm by changing stdin to
     non-blocking). (Nikita)
 
+- PCRE:
+  . Fixed bug #76512 (\w no longer includes unicode characters). (cmb)
+
 - Standard:
   . Fixed bug #76505 (array_merge_recursive() is duplicating sub-array keys).
     (Laruence)

ext/pcre/php_pcre.c

@@ -672,8 +672,8 @@ PHPAPI pcre_cache_entry* pcre_get_compiled_regex_cache(zend_string *regex)
 			case 'u':	coptions |= PCRE2_UTF;
 	/* In  PCRE,  by  default, \d, \D, \s, \S, \w, and \W recognize only ASCII
        characters, even in UTF-8 mode. However, this can be changed by setting
-       the PCRE_UCP option. */
-#ifdef PCRE_UCP
+       the PCRE2_UCP option. */
+#ifdef PCRE2_UCP
 						coptions |= PCRE2_UCP;
 #endif
 				break;

ext/pcre/tests/bug52971.phpt

@@ -19,15 +19,8 @@ var_dump($match);
 --EXPECT--
 array(1) {
   [0]=>
-  array(2) {
+  array(1) {
     [0]=>
-    array(2) {
-      [0]=>
-      string(6) "wasser"
-      [1]=>
-      int(17)
-    }
-    [1]=>
     array(2) {
       [0]=>
       string(6) "Wasser"
@@ -38,15 +31,8 @@ array(1) {
 }
 array(1) {
   [0]=>
-  array(2) {
+  array(1) {
     [0]=>
-    array(2) {
-      [0]=>
-      string(8) "ßwasser"
-      [1]=>
-      int(15)
-    }
-    [1]=>
     array(2) {
       [0]=>
       string(7) " Wasser"

ext/pcre/tests/bug76512.phpt

@@ -0,0 +1,10 @@
+--TEST--
+Bug #76512 (\w no longer includes unicode characters)
+--FILE--
+<?php
+var_dump(preg_match('/\w/u', 'ä'));
+?>
+===DONE===
+--EXPECT--
+int(1)
+===DONE===