gcc: depend on zstd

gcc: depend on zstd

Add zstd LTO support for target and nativesdk compiler.
This also brings gcc into sync with gcc-cross.

% x86_64-oe-linux-gcc -v
[...]
 Supported LTO compression algorithms: zlib zstd
 gcc version 12.2.0 (GCC)
% x86_64-oesdk-linux-gcc -v
[...]
 Supported LTO compression algorithms: zlib
 gcc version 12.2.0 (GCC)

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>