New comment by mintsuki on void-packages repository

https://github.com/void-linux/void-packages/pull/31658#issuecomment-868998211

Comment:
```
In file included from ../../../gcc-11.1.0/libgcc/libgcov-merge.c:26:
../../../gcc-11.1.0/libgcc/libgcov.h:49:10: fatal error: sys/mman.h: No such file or directory
   49 | #include <sys/mman.h>
      |          ^~~~~~~~~~~~
```
Can not find `sys/mman.h`? That surely is odd; am I missing something?