use true/false instead of 1/0 detected and changed by clang-tidy

src/read_data.cpp

@@ -430,7 +430,7 @@ void ReadData::command(int narg, char **arg)
   nlocal_previous = atom->nlocal;
   int firstpass = 1;
 
-  while (1) {
+  while (true) {
 
     // open file on proc 0
 
@@ -965,7 +965,7 @@ void ReadData::header(int firstpass)
     if (eof == nullptr) error->one(FLERR,"Unexpected end of data file");
   }
 
-  while (1) {
+  while (true) {
 
     // read a line and bcast length