disable running embossupdate on installation of EMBOSS (may fail to connect to EMBOSSupdates DB)

ran into this issue during `make install` of EMBOSS:

```
/path/to/software/EMBOSS/6.5.7-goolf-1.4.10/bin/embossupdate
Checks for more recent updates to EMBOSS
Error: socket connect failed for database 'EMBOSSupdates'
socket connect failed for database 'EMBOSSupdates': Connection timed out
Error: ajHttpRead: cannot open HTTP connection 'GET /updates/EMBOSS.fixes HTTP/1.1
```

this patch disables the `embossupdate` during `make install`

it's pretty much useless anyway, since it only reports whether updates are availabel