Fix typo in platform macro defines for examples
diff --git a/programs/x509/crl_app.c b/programs/x509/crl_app.c
index 687752f..f831683 100644
--- a/programs/x509/crl_app.c
+++ b/programs/x509/crl_app.c
@@ -31,7 +31,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #define mbedtls_printf          printf
-#define MBEDTLS_EXTI_SUCCESS    EXIT_SUCCESS
+#define MBEDTLS_EXIT_SUCCESS    EXIT_SUCCESS
 #define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
 #endif /* MBEDTLS_PLATFORM_C */