nfs: Remove unneeded checking of the return value from scnprintf

The return value from scnprintf always less than the buffer length.
So, result >= len always false. This patch removes those checking.

int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
        int i;

	i = vsnprintf(buf, size, fmt, args);

	if (likely(i < size))
		return i;
	if (size != 0)
		return size - 1;
	return 0;
}

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>