arm-none-eabi-gcc: update to 14.2.0

This makes it possible to build arm-none-eabi-gcc using the Xcode 16
toolchain, enabling macOS 15 support. gcc 14 is currently the only gcc
version that can build under Xcode 16/macOS 15.

Closes: https://trac.macports.org/ticket/70754

cross/arm-none-eabi-gcc/Portfile

@@ -3,7 +3,7 @@
 PortSystem          1.0
 PortGroup           crossgcc 1.0
 
-set gccversion      13.2.0
+set gccversion      14.2.0
 set newlibversion   4.3.0.20230120
 crossgcc.setup      arm-none-eabi ${gccversion}
 crossgcc.setup_libc newlib ${newlibversion}