fix help message issues

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/programs/test/query_compile_time_config.c b/programs/test/query_compile_time_config.c
index 0bc9dee..6d92de3 100644
--- a/programs/test/query_compile_time_config.c
+++ b/programs/test/query_compile_time_config.c
@@ -29,13 +29,13 @@
 #endif
 
 #define USAGE                                                                \
-    "usage: %s <MBEDTLS_CONFIG> | -l\n\n"                                    \
+    "usage: %s [ <MBEDTLS_CONFIG> | -l ]\n\n"                                \
     "This program takes one command line argument which corresponds to\n"    \
     "the string representation of a Mbed TLS compile time configuration.\n"  \
     "The value 0 will be returned if this configuration is defined in the\n" \
     "Mbed TLS build and the macro expansion of that configuration will be\n" \
     "printed (if any). Otherwise, 1 will be returned.\n"                     \
-    "-l\tPrint all available configuration"
+    "-l\tPrint all available configuration.\n"
 #include <string.h>
 #include "query_config.h"