Fix typos prior to release

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index 9cd70d4..ab04648 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.c
@@ -358,7 +358,7 @@
     if( ( ret = write_certificate_request( &req, opt.output_file,
                                            mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  !  write_certifcate_request %d", ret );
+        mbedtls_printf( " failed\n  !  write_certificate_request %d", ret );
         goto exit;
     }