Linux: Move wordsize-32 Version to default

And remove redundant entries on other architectures Version.  The
version for fallocate64 was supposed to be 2.10, but it was then
added to 32-bit platforms in 2.11 because it mistakenly wasn't
exported for them in  2.10 (see the commit message for
1f3615a1).

The linux/generic did not exist before 2.15, i.e. when the tile
ports were added (and microblaze did not exist before 2.18), which
explains those differences but also illustrates that "2.11 for 32-bit,
2.10 for 64-bit" should be sufficient since versions older than the
minimum for the architecture are automatically adjusted.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>