build+docs: recommend Xcode 13 or later

We are not testing Xcode 12 / macOS 11 in CI anymore

Change-Id: I2f27caa25612faa96463524ea0249899301c2cf5
diff --git a/docs/INSTALL.rst b/docs/INSTALL.rst
index 835b028..2f57b9b 100644
--- a/docs/INSTALL.rst
+++ b/docs/INSTALL.rst
@@ -9,10 +9,11 @@
 
 - Ubuntu 20.04 (focal)
 - Ubuntu 22.04 (jammy)
+- Ubuntu 24.04 (noble)
 - Debian 11 (bullseye)
 - Debian 12 (bookworm)
 - CentOS Stream 9
-- macOS 11 / 12 / 13 / 14
+- macOS 12 / 13 / 14
 
 NFD should also work on the following platforms, although they are not officially
 supported:
@@ -21,7 +22,7 @@
 - Fedora >= 33
 - Alpine >= 3.12
 - Any version of Raspberry Pi OS based on Debian 11 (bullseye) or later
-- macOS 10.15
+- macOS >= 10.15
 - FreeBSD >= 12.2
 
 .. _Install NFD on Ubuntu Linux using the NDN PPA repository: