padata: free correct variable

The author meant to free the variable that was just allocated, instead
of the one that failed to be allocated, but made a simple typo. This
patch rectifies that.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>