- Use valid tarball FTP url.

- Update to v4.3.0
* remove i?86-pc-linux-gnu support
* remove decstation & sunos support
* remove phoenix OS support
* remove unused members from struct _reent (see also
--enable-newlib-reent-binary-compat)
* build system internals heavily rewritten & updated
* make arm jmp_buf size and alignment ABI-conformant
* fixed bug in arm setjmp/longjmp to preserve floating-point register
values
* add --enable-newlib-reent-thread-local configuration option
* add --enable-newlib-reent-binary-compat configuration option
* add 64-bit powerpc setjmp/longjmp support
* use global stdio streams for all configurations
* use global atexit data for all configurations
* vectorized math routines added for amdgcn platform
* nvptx: remove newlib ELIX level 1 restriction
- Already in v4.2.0
* remove use of --cygnus option for automake
* rename configure.in files to configure.ac
* enable automake silent rules
* import gdtoa from OpenBSD
* update to Unicode 14.0
* ignore _FORTIFY_SOURCE when building newlib
* fixes to ldtoa
* add clock support to nvptx port
* various pthread POSIX APIs added
* added implementatio for sig2str/str2sig