Revert "SUNRPC: clean up integer overflow check"

This reverts commit e87cf8a2.

This commit was added to silence a tautological comparison warning, but
removing the 'len' value check before calling xdr_inline_decode() is
really not what we want.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

include/linux/sunrpc/xdr.h

@@ -779,7 +779,9 @@ xdr_stream_decode_uint32_array(struct xdr_stream *xdr,
 
 	if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
 		return -EBADMSG;
-	p = xdr_inline_decode(xdr, size_mul(len, sizeof(*p)));
+	if (len > SIZE_MAX / sizeof(*p))
+		return -EBADMSG;
+	p = xdr_inline_decode(xdr, len * sizeof(*p));
 	if (unlikely(!p))
 		return -EBADMSG;
 	if (array == NULL)