kprobes/x86: Free 'optinsn' cache when range check fails

kprobes/x86: Free 'optinsn' cache when range check fails

This patch frees the 'optinsn' slot when we get a range check error,
to prevent memory leaks.

Before this patch, cache entry in kprobe_insn_cache() won't be freed
if kprobe optimizing fails due to range check failure.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Pei Feiyue <peifeiyue@huawei.com>
Link: http://lkml.kernel.org/r/1406550019-70935-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>