testing/splitter: disable on aarch64

This failed on the aarch64 package builder

hare build -lcairo -lm -ldl -lbz2 -lpthread -lbsd -lmd -lxkbcommon -lfontconfig -lexpat -lm -lfreetype -lbz2 -lpng16 -lz -lbrotlidec -lbrotlicommon -lXext -lXrender -lX11 -lpthread -lxcb-render -lx
cb-shm -lxcb -lXau -lXdmcp -lpixman-1 -lm -o splitterui cmd/splitterui/
wayland.ha:115:22: error: Initializer is not assignable to struct field
wayland.ha:387:18: error: Initializer is not assignable to struct field
harec for /home/buildozer/aports/testing/splitter/src/splitter-0.1.0/cmd/splitterui exited with status 1
make: *** [Makefile:55: splitterui] Error 255

disabling for now.

!53234 (merged)