crypto: ccp - Refactor code to enable checks for queue space.

Available queue space is used to decide (by counting free slots)
if we have to put a command on hold or if it can be sent
to the engine immediately.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/ccp/ccp-dev.h

@@ -458,6 +458,7 @@ struct ccp_actions {
 	u32 (*sballoc)(struct ccp_cmd_queue *, unsigned int);
 	void (*sbfree)(struct ccp_cmd_queue *, unsigned int,
 			       unsigned int);
+	unsigned int (*get_free_slots)(struct ccp_cmd_queue *);
 	int (*init)(struct ccp_device *);
 	void (*destroy)(struct ccp_device *);
 	irqreturn_t (*irqhandler)(int, void *);