R-tzdb, R-Hmisc: fix-ups for 10.7–10.12

[barracuda156]

Description

R-tzdb does not build on 10.7–10.11 due to r-lib/tzdb#34
https://ports.macports.org/port/R-tzdb/details
Conditionally revert the commit that has broken the build: r-lib/tzdb@a1ed5c0

R-Hmisc fails on 10.12, for w/e reason: https://ports.macports.org/port/R-Hmisc/details
Since there is a new version, upgrade and see if the issue is fixed.

Type(s)

• bugfix
• enhancement
• security fix

Tested on

macOS 10.6
Xcode 3.2

Verification

Have you

• followed our Commit Message Guidelines?
• squashed and minimized your commits?
• checked that there aren't other open pull requests for the same change?
• referenced existing tickets on Trac with full URL?
• checked your Portfile with port lint --nitpick?
• tried existing tests with sudo port test?
• tried a full install with sudo port -vst install?
• tested basic functionality of all binary files?
• checked that the Portfile's most important variants haven't been broken?