ftrace/scripts: Fix incorrect use of sprintf in recordmcount

Fix build warning:

scripts/recordmcount.c:589:4: warning: format not a string
literal and no format arguments [-Wformat-security]
    sprintf("%s: failed\n", file);

Fixes: a50bd439

 ("ftrace/scripts: Have recordmcount copy the object file")
Link: http://lkml.kernel.org/r/1451516801-16951-1-git-send-email-colin.king@canonical.com

Cc: Li Bin <huawei.libin@huawei.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org # 2.6.37+
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>