crypto: pcrypt - Call crypto layer directly when padata_do_parallel() return -EBUSY

Since commit 8f4f68e7 ("crypto: pcrypt - Fix hungtask for
PADATA_RESET"), the pcrypt encryption and decryption operations return
-EAGAIN when the CPU goes online or offline. In alg_test(), a WARN is
generated when pcrypt_aead_decrypt() or pcrypt_aead_encrypt() returns
-EAGAIN, the unnecessary panic will occur when panic_on_warn set 1.
Fix this issue by calling crypto layer directly without parallelization
in that case.

Fixes: 8f4f68e7 ("crypto: pcrypt - Fix hungtask for PADATA_RESET")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>