Add include for u_strToLower and others

diff --git a/src/icu_casemap.c b/src/icu_casemap.c
index 4c50f69..2ee7ebf 100644 (file)
--- a/src/icu_casemap.c
+++ b/src/icu_casemap.c
@@ -23,6 +23,8 @@
 #include <stdlib.h>
 #include <stdio.h>
 
+#include <unicode/ustring.h>
+
 struct icu_casemap
 {
     char action;