RPC framework: Use the dedicated eRPC config file

Change-Id: I906fdca6a0d10c747ddd92a0c008bebb22ad0a77
Signed-off-by: Kevin Peng <kevin.peng@arm.com>
diff --git a/app/erpc_app.c b/app/erpc_app.c
index af87f94..3ea7b86 100644
--- a/app/erpc_app.c
+++ b/app/erpc_app.c
@@ -8,7 +8,7 @@
 #include "test_app.h"
 #include "tfm_log.h"
 #include "erpc_server_start.h"
-#include "target_cfg.h"
+#include "config_erpc_target.h"
 
 #include "Driver_USART.h"
 #ifdef ERPC_UART