caprotocol: fix typo in protocol description

The commit specifies the name of the server (S) that is later used in
the description.

Also, it adds the missing 'i' in the word 'finIshed' and fixes the
multi-line comment by removing the unnecessary leading '* ' before
closing the comment.

src/caprotocol.h

@@ -23,7 +23,7 @@ enum {
 
 /* Protocol description:
  *
- * Client C connects to server:
+ * Client C connects to server S:
  *
  * Both C and S immediately send CA_PROTOCOL_HELLO:
  *      C → S: CA_PROTOCOL_HELLO
@@ -40,7 +40,7 @@ enum {
  *      C → S: CA_PROTOCOL_REQUEST
  *      S → C: CA_PROTOCOL_CHUNK
  *
- *      Finshed by:
+ *      Finished by:
  *      C → S: CA_PROTOCOL_GOODBYE (optional)
  *
  * On push:
@@ -60,7 +60,7 @@ enum {
  * When a non-recoverable error occurs, either side can send CA_PROTOCOL_ABORTED with an explanation, and terminate the
  * connection.
  *
- * */
+ */
 
 typedef struct CaProtocolHeader {
         le64_t size;