ibmpc & Intel systems: Fix coverity identified issues

Intel-Systems/common/i8080.c

@@ -1320,6 +1320,7 @@ t_stat parse_sym (CONST char *cptr, t_addr addr, UNIT *uptr, t_value *val, int32
     int32 cflag, i = 0, j, r;
     char gbuf[CBUFSIZE];
 
+    memset (gbuf, 0, sizeof (gbuf));
     cflag = (uptr == NULL) || (uptr == &i8080_unit);
     while (isspace (*cptr)) cptr++;                         /* absorb spaces */
     if ((sw & SWMASK ('A')) || ((*cptr == '\'') && cptr++)) { /* ASCII char? */
@@ -1337,7 +1338,7 @@ t_stat parse_sym (CONST char *cptr, t_addr addr, UNIT *uptr, t_value *val, int32
    or numeric (including spaces).
 */
 
-    while (1) {
+    while (i < sizeof (gbuf) - 4) {
         if (*cptr == ',' || *cptr == '\0' ||
              isdigit(*cptr))
                 break;