[tracker] Use g_strstr_len() instead of GNU extension memmem.

[Antoine Jacoutot <ajacoutot src gnome org>]

commit cdae3a22e7a0001df7877e4ee3531e26158a6d56
Author: Antoine Jacoutot <ajacoutot gnome org>
Date:   Thu Apr 11 13:16:05 2013 +0200

    Use g_strstr_len() instead of GNU extension memmem.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=697780

 src/tracker-extract/tracker-extract-mp3.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/tracker-extract/tracker-extract-mp3.c b/src/tracker-extract/tracker-extract-mp3.c
index 9b154f9..9189028 100644
--- a/src/tracker-extract/tracker-extract-mp3.c
+++ b/src/tracker-extract/tracker-extract-mp3.c
@@ -1049,10 +1049,10 @@ id3v2_strlen (const gchar  encoding,
        case 0x02:
                
                /* UTF-16, string terminated by two NUL bytes */
-               pos = memmem (text, len, "\0\0\0", 3);
+               pos = g_strstr_len (text, len, "\0\0\0");
 
                if (pos == NULL) {
-                       pos = memmem (text, len, "\0\0", 2);
+                       pos = g_strstr_len (text, len, "\0\0");
                } else {
                        pos++;
                }