devel/cctz: Update to 2.4

• Switch to CMake
• Backport upstream commit 64d12062183e2fa01f8c0127c4b9f91afaeee46c
• Import patches from Debian
• Build shared library instead of static
• Rework Makefile to follow Porters Handbook more closely

References:
https://github.com/google/cctz/commit/64d12062183e2fa01f8c0127c4b9f91afaeee46c

Sources:
https://salsa.debian.org/science-team/cctz/-/blob/master/debian/patches/0001-Compile-shared-lib-and-install-it.patch?ref_type=heads
https://salsa.debian.org/science-team/cctz/-/blob/master/debian/patches/use_system_zoneinfo.patch?ref_type=heads

PR: 261879
Approved by: portmgr (maintainer timeout, 2+ years)