installation/guides/chroot: improve the fstab section

[r-ricci]

From mount(8):

rw
Mount the filesystem read-write.

noatime
Do not update inode access times on this filesystem (e.g. for faster access on the news spool to speed up news servers). This works for all inode types (directories too), so it implies nodiratime.

Swap is not a filesytem and it doesn't have inodes, so these options are useless.

Since this is just an example, it's ok if it is opinionated, equal to the defaults or not suitable for all use cases, but it should not be wrong or irrelevant.

[classabbyamp]

the installer does this: https://github.com/void-linux/void-mklive/blob/master/installer.sh.in#L1042

[r-ricci]

the installer does this: https://github.com/void-linux/void-mklive/blob/master/installer.sh.in#L1042

I think it's better if the examples are aligned to what the installer does, for the other fstab entries too.

However, after reading the mount(8), fstab(5) and swapon(8) man pages and performing a quick search on the web, it turns out that sw is also meaningless (and ignored) on Linux, despite being widely used. It has a meaning on (some?) *BSD systems, where it is more or less equivalent to auto.

So I believe the installer should be changed. Unless specific options are required (e.g.: discard, pri), the last three fields could be dropped entirely. If specifying all the fields is preferred, I think defaults is the most sensible placeholder.

[r-ricci]

ping

[Duncaen]

fstab entries should be ordered, the current example is already wrong.

[classabbyamp]

this section no longer exists with #826