pk: fix typos in description of mbedtls_pk_setup_opaque()

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index a3b1363..a239270 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -361,10 +361,10 @@
 /**
  * \brief Initialize a PK context to wrap a PSA key.
  *
- * This function helps creating a PK context which wraps a PSA key. The PSA wrapped
- * key must be an EC or RSA key pair (DH is not suported in PK module).
+ * This function creates a PK context which wraps a PSA key. The PSA wrapped
+ * key must be an EC or RSA key pair (DH is not suported in the PK module).
  *
- * Under the hood PSA functions are used to perform the required
+ * Under the hood PSA functions will be used to perform the required
  * operations and, based on the key type, used algorithms will be:
  * * EC:
  *     * verify, verify_ext, sign, sign_ext: ECDSA.