x11/tilix: disable SSP unsupported by lang/ldc

meson.build:1:0: ERROR: Unable to detect linker for compiler ldc2 -L=--version /tmp/tmpo84ihqx4.d -fstack-protector-strong
stdout:
stderr: ldc2: Unknown command line argument '-fstack-protector-strong'. Try: 'ldc2 --help'
ldc2: Did you mean '--stack-symbol-ordering'?

PR: 264776
Reported by: antoine (via exp-run)
Regressed by: https://github.com/mesonbuild/meson/commit/235c78682e82