Test driver: keep variable declarations first

Followed by hook calls, and sanity checks last.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/tests/src/drivers/test_driver_key_management.c b/tests/src/drivers/test_driver_key_management.c
index 5b3bab6..89cb8b9 100644
--- a/tests/src/drivers/test_driver_key_management.c
+++ b/tests/src/drivers/test_driver_key_management.c
@@ -169,14 +169,14 @@
     size_t *key_buffer_length,
     size_t *bits)
 {
+    psa_key_type_t type = psa_get_key_type( attributes );
+
     ++mbedtls_test_driver_key_management_hooks.hits;
     mbedtls_test_driver_key_management_hooks.location = PSA_KEY_LOCATION_LOCAL_STORAGE;
 
     if( mbedtls_test_driver_key_management_hooks.forced_status != PSA_SUCCESS )
         return( mbedtls_test_driver_key_management_hooks.forced_status );
 
-    psa_key_type_t type = psa_get_key_type( attributes );
-
     if( PSA_KEY_TYPE_IS_ECC( type ) )
     {
 #if defined(MBEDTLS_TEST_LIBTESTDRIVER1) && \
@@ -232,15 +232,15 @@
     const uint8_t *key, size_t key_length,
     uint8_t *data, size_t data_size, size_t *data_length )
 {
+    /* Assume this is a builtin key based on the key material length. */
+    psa_drv_slot_number_t slot_number = *( ( psa_drv_slot_number_t* ) key );
+
     if( key_length != sizeof( psa_drv_slot_number_t ) )
     {
         /* Test driver does not support generic opaque key handling yet. */
         return( PSA_ERROR_NOT_SUPPORTED );
     }
 
-    /* Assume this is a builtin key based on the key material length. */
-    psa_drv_slot_number_t slot_number = *( ( psa_drv_slot_number_t* ) key );
-
     switch( slot_number )
     {
         case PSA_CRYPTO_TEST_DRIVER_BUILTIN_ECDSA_KEY_SLOT: