log: Only print one space if no level selected

Prior to this change, when no "level" option is given to the logging
module, we see

    [PHY]   RU 0 RF started cpu_meas_enabled 0
    [HW]   No connected device, generating void samples...

with three spaces, which is too much. This change reduces the amount of
spaces to 1 without log level.

Co-authored-by: Robert Schmidt <robert.schmidt@openairinterface.org>

common/utils/LOG/log.h

@@ -217,7 +217,7 @@ typedef struct  {
 typedef struct {
   log_component_t         log_component[MAX_LOG_COMPONENTS];
   log_component_back_t log_rarely_used[MAX_LOG_COMPONENTS];
-  char                    level2string[NUM_LOG_LEVEL];
+  char level2string[NUM_LOG_LEVEL][4];
   int                     flag;
   char                   *filelog_name;
   debug_flags_t debug_mask;