Rename mbedtls_zeroize to mbedtls_platform_zeroize
diff --git a/library/pk.c b/library/pk.c
index bd3e427..f05b139 100644
--- a/library/pk.c
+++ b/library/pk.c
@@ -29,7 +29,7 @@
 #include "mbedtls/pk.h"
 #include "mbedtls/pk_internal.h"
 
-#include "mbedtls/utils.h"
+#include "mbedtls/platform_util.h"
 
 #if defined(MBEDTLS_RSA_C)
 #include "mbedtls/rsa.h"
@@ -66,7 +66,7 @@
 
     ctx->pk_info->ctx_free_func( ctx->pk_ctx );
 
-    mbedtls_zeroize( ctx, sizeof( mbedtls_pk_context ) );
+    mbedtls_platform_zeroize( ctx, sizeof( mbedtls_pk_context ) );
 }
 
 /*