[llvm-profgen] Ignore invalid perf line in LBR record

Similar to https://reviews.llvm.org/D109637, there is a whole invalid line of message in perfscript.

```
warning: Invalid address in LBR record at line 14118674: Processed 14138923 events and lost 1 chunks!
warning: Invalid address in LBR record at line 14118676: Check IO/CPU overload!
```

This only happened for LBR only perfscript, hybridperfscript have a check of " 0x" to make sure it's the LBR perf line.

Reviewed By: hoy, wenlei

Differential Revision: https://reviews.llvm.org/D110424