Fix misleading sub-state name and comments

The enum constant had 'ske' in its name while this was a sub-state of the
"write client key exchange" state; corresponding issue in the comment.
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 7b88e61..5720a4b 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2946,7 +2946,7 @@
 #if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
         if( ssl->handshake->ecrs_enabled )
         {
-            if( ssl->handshake->ecrs_state == ssl_ecrs_ske_ecdh_calc_secret )
+            if( ssl->handshake->ecrs_state == ssl_ecrs_cke_ecdh_calc_secret )
                 goto ecdh_calc_secret;
 
             mbedtls_ecdh_enable_restart( &ssl->handshake->ecdh_ctx );
@@ -2973,7 +2973,7 @@
         if( ssl->handshake->ecrs_enabled )
         {
             ssl->handshake->ecrs_n = n;
-            ssl->handshake->ecrs_state = ssl_ecrs_ske_ecdh_calc_secret;
+            ssl->handshake->ecrs_state = ssl_ecrs_cke_ecdh_calc_secret;
         }
 
 ecdh_calc_secret: