build: optimise arm64 darwin qt build using -O1

Building at higher optimisation levels causes reproducibility issues
when building on different architectures.

Author: fanquake

depends/packages/qt.mk

@@ -131,6 +131,9 @@ $(package)_config_opts_darwin += -no-feature-corewlan
 $(package)_config_opts_darwin += -no-freetype
 $(package)_config_opts_darwin += QMAKE_MACOSX_DEPLOYMENT_TARGET=$(OSX_MIN_VERSION)
 
+# Optimizing using > -O1 causes non-determinism when building across arches.
+$(package)_config_opts_aarch64_darwin += "QMAKE_CFLAGS_OPTIMIZE_FULL = -O1"
+
 ifneq ($(build_os),darwin)
 $(package)_config_opts_darwin += -xplatform macx-clang-linux
 $(package)_config_opts_darwin += -device-option MAC_SDK_PATH=$(OSX_SDK)