crypto: ccp - Fix ccp_run_passthru_cmd dma variable assignments

There are some suspicious looking lines of code in the new ccp driver, including
one that assigns a variable to itself, and another that overwrites a previous assignment.

This may have been a cut-and-paste error where 'src' was forgotten to be changed to 'dst'.
I have no hardware to test this, so this is untested.

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>