samples: psa_leve1: do not re-initialize NS interface

TF-M NS interface is initialized by the TF-M module
code, so it does not need to be re-initialized in the
sample code.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>

samples/tfm_integration/psa_level_1/src/main.c

@@ -23,9 +23,6 @@ static struct cfg_data cfg;
 
 void main(void)
 {
-	/* Initialize the TFM NS interface */
-	tfm_ns_interface_init();
-
 	/* Initialise the logger subsys and dump the current buffer. */
 	log_init();