Update ICU to 58.1

source/i18n/unicode/usearch.h

Index: source/i18n/unicode/usearch.h
diff --git a/source/i18n/unicode/usearch.h b/source/i18n/unicode/usearch.h
index 75521f528a410fae192358b070f38590d6626a3d..b1d53f512d86ab5458bf154c889c67332b26f6cc 100644
--- a/source/i18n/unicode/usearch.h
+++ b/source/i18n/unicode/usearch.h
@@ -1,3 +1,5 @@
+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
 /*
 **********************************************************************
 *   Copyright (C) 2001-2011,2014 IBM and others. All rights reserved.
@@ -188,11 +190,13 @@ typedef enum {
      */
     USEARCH_ELEMENT_COMPARISON = 2,
 
+#ifndef U_HIDE_DEPRECATED_API
     /**
-     * Count of attribute types
-     * @stable ICU 2.4
+     * One more than the highest normal USearchAttribute value.
+     * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
      */
     USEARCH_ATTRIBUTE_COUNT = 3
+#endif  // U_HIDE_DEPRECATED_API
 } USearchAttribute;
 
 /**
@@ -262,11 +266,13 @@ typedef enum {
      */
     USEARCH_ANY_BASE_WEIGHT_IS_WILDCARD,
 
+#ifndef U_HIDE_DEPRECATED_API
     /**
-     * Count of attribute values
-     * @stable ICU 2.4
+     * One more than the highest normal USearchAttributeValue value.
+     * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
      */
     USEARCH_ATTRIBUTE_VALUE_COUNT
+#endif  // U_HIDE_DEPRECATED_API
 } USearchAttributeValue;
 
 /* open and close ------------------------------------------------------ */