databases/influxdb: fix build on riscv64

[fuz]

Summary

Preliminary patch for maintainer approval.

databases/influxdb: fix build on riscv64

Bump golang.org/x/sys dependency to a version new enough to
support riscv64-freebsd.

Sponsored by:	Berliner Linux User Group e.V.
Approved by:	portmgr (build fix blanket)
Approved by:	... (mentor)

Test Plan

Tested manually on riscv64 FreeBSD 13.1.
Will test with Poudriere on amd64 i386 arm64 FreeBSD 12.4 13.1.

[driesm]

I am wondering if any of these changes for riscv64 are upstreamable? Diff is quite large.

[fuz]

It appears that upstream has already fixed the issue in its git repository, so with the next upstream release, this patch should be obsolete.