PKCS11: Rename mbedtls_pk_xxx functions

Rename mbedtls_pk_setup_pkcs11 and mbedtls_pk_import_to_pkcs11
to reflect the proper namespace they are in.
diff --git a/library/pkcs11_client.c b/library/pkcs11_client.c
index 1e662f8..e1b7e6d 100644
--- a/library/pkcs11_client.c
+++ b/library/pkcs11_client.c
@@ -327,7 +327,7 @@
                               , NULL //debug_func
         );
 
-int mbedtls_pk_setup_pkcs11( mbedtls_pk_context *ctx,
+int mbedtls_pkcs11_setup_pk( mbedtls_pk_context *ctx,
                              CK_SESSION_HANDLE hSession,
                              CK_OBJECT_HANDLE hPublicKey,
                              CK_OBJECT_HANDLE hPrivateKey )
@@ -438,7 +438,7 @@
 
 #define MBEDTLS_PKCS11_BOOL( x ) ( ( x ) ? CK_TRUE : CK_FALSE )
 
-int mbedtls_pk_import_to_pkcs11( const mbedtls_pk_context *ctx,
+int mbedtls_pkcs11_import_pk( const mbedtls_pk_context *ctx,
                                  uint32_t flags,
                                  CK_SESSION_HANDLE hSession,
                                  CK_OBJECT_HANDLE *hPublicKey,