Make the fields of mbedtls_ecp_curve_info public

The whole point of this structure is to provide information, both for the
library's own sake and to applications.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/programs/pkey/gen_key.c b/programs/pkey/gen_key.c
index 4043dfa..7535eee 100644
--- a/programs/pkey/gen_key.c
+++ b/programs/pkey/gen_key.c
@@ -86,7 +86,7 @@
 #endif
 
 #if defined(MBEDTLS_ECP_C)
-#define DFL_EC_CURVE            mbedtls_ecp_curve_list()->MBEDTLS_PRIVATE(grp_id)
+#define DFL_EC_CURVE            mbedtls_ecp_curve_list()->grp_id
 #else
 #define DFL_EC_CURVE            0
 #endif
@@ -219,9 +219,9 @@
 #if defined(MBEDTLS_ECP_C)
         mbedtls_printf( " available ec_curve values:\n" );
         curve_info = mbedtls_ecp_curve_list();
-        mbedtls_printf( "    %s (default)\n", curve_info->MBEDTLS_PRIVATE(name) );
-        while( ( ++curve_info )->MBEDTLS_PRIVATE(name) != NULL )
-            mbedtls_printf( "    %s\n", curve_info->MBEDTLS_PRIVATE(name) );
+        mbedtls_printf( "    %s (default)\n", curve_info->name );
+        while( ( ++curve_info )->name != NULL )
+            mbedtls_printf( "    %s\n", curve_info->name );
 #endif /* MBEDTLS_ECP_C */
         goto exit;
     }
@@ -270,7 +270,7 @@
         {
             if( ( curve_info = mbedtls_ecp_curve_info_from_name( q ) ) == NULL )
                 goto usage;
-            opt.ec_curve = curve_info->MBEDTLS_PRIVATE(grp_id);
+            opt.ec_curve = curve_info->grp_id;
         }
 #endif
         else if( strcmp( p, "filename" ) == 0 )
@@ -391,7 +391,7 @@
     {
         mbedtls_ecp_keypair *ecp = mbedtls_pk_ec( key );
         mbedtls_printf( "curve: %s\n",
-                mbedtls_ecp_curve_info_from_grp_id( ecp->MBEDTLS_PRIVATE(grp).id )->MBEDTLS_PRIVATE(name) );
+                mbedtls_ecp_curve_info_from_grp_id( ecp->MBEDTLS_PRIVATE(grp).id )->name );
         mbedtls_mpi_write_file( "X_Q:   ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(X), 16, NULL );
         mbedtls_mpi_write_file( "Y_Q:   ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(Y), 16, NULL );
         mbedtls_mpi_write_file( "D:     ", &ecp->MBEDTLS_PRIVATE(d)  , 16, NULL );