Invalid name records in Gentium Book Basic

**Describe the bug**
The encoding of entries in the naming table contradicts the [specification](https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6name.html). More specifically, for some entries, the platform is set to be Mac, that is, 1, but the language tags follow Windows, such as 0x409 for United States English.

**To Reproduce**
For instance, using `fonttools`:

```shell
ttx -t name ofl/gentiumbookbasic/GenBkBasI.ttf
cat ofl/gentiumbookbasic/GenBkBasI.ttx | grep 2048
#
#
```

It can be seen that the platform is Mac, but the language ID is 0x409, which is a value outside of the range of the languages on that platform. The last language on Mac has a code of 150. The 0x409 seems to come from the table for Windows where this value corresponds to United States English. Therefore, the language ID does not agree with the platform ID.

**Expected behavior**
The platforms and languages should agree.