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