AMS Sansa: Handle responses to SD Commands so that response crc checking is accounted for. Adjust sd error codes appropriately.
The crc check on responses to sd commands was being bypassed due to a SD_APP_OP_COND special case. Now a short response is returned
even if the crc check fails so we can check the busy bit. The send_cmd() function still returns a false value but it loads the response
variable with the cmd response.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23718 a1c6a512-1295-4272-9138-f99709370657