crypto: algapi - Remove unneeded null check

We don't check "frontend" consistently in crypto_init_spawn2().  We
check it at the start of the function but then we dereference it
unconditionally in the parameter list when we call crypto_init_spawn().

I looked at the places that call crypto_init_spawn2() and "frontend" is
always a valid pointer so I removed the check for null.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>