fix log-mem issue to be useful even if you didnot set log-mem in config file

targets/RT/USER/lte-softmodem-common.c

@@ -58,6 +58,7 @@ void get_common_options(void) {
   uint32_t noS1;
   uint32_t nokrnmod;
   uint32_t nonbiot;
+  char *logmem_filename = NULL;
   paramdef_t cmdline_params[] =CMDLINE_PARAMS_DESC ;
   paramdef_t cmdline_logparams[] =CMDLINE_LOGPARAMS_DESC ;
   checkedparam_t cmdline_log_CheckParams[] = CMDLINE_LOGPARAMS_CHECK_DESC;
@@ -78,7 +79,7 @@ void get_common_options(void) {
     load_module_shlib("telnetsrv",NULL,0,NULL);
   }
 
-  if (strlen(logmem_filename) > 0) {
+  if (logmem_filename != NULL && strlen(logmem_filename) > 0) {
     log_mem_filename = &logmem_filename[0];
     log_mem_flag = 1;
     printf("Enabling OPT for log save at memory %s\n",log_mem_filename);

targets/RT/USER/lte-softmodem.h

@@ -225,7 +225,7 @@
     {"g" ,           CONFIG_HLP_LOGL, 0,      uptr:&glog_level,     defintval:0,         TYPE_UINT,     0},        \
     {"telnetsrv",        CONFIG_HLP_TELN, PARAMFLAG_BOOL,   uptr:&start_telnetsrv,    defintval:0,         TYPE_UINT,     0},        \
     {"msc",                CONFIG_HLP_MSC,  PARAMFLAG_BOOL,   uptr:&START_MSC,            defintval:0,         TYPE_UINT,     0},                    \
-    {"log-mem",                       NULL,                  0,                strptr:(char **)&logmem_filename,    defstrval:"./logmem.log",          TYPE_STRING,   sizeof(logmem_filename)},    \
+    {"log-mem",      NULL,            0,      strptr:(char **)&logmem_filename,    defstrval:NULL,          TYPE_STRING,   0},    \
   }
 #define CMDLINE_ONLINELOG_IDX     0
 #define CMDLINE_GLOGLEVEL_IDX     1