Fix Qt's rcc determinism for depends/gitian

Backport of https://bugreports.qt.io/browse/QTBUG-62511 to resolve
locale determinism during the build process.

depends/packages/qt.mk

@@ -8,7 +8,7 @@ $(package)_dependencies=openssl zlib
 $(package)_linux_dependencies=freetype fontconfig libxcb libX11 xproto libXext
 $(package)_build_subdir=qtbase
 $(package)_qt_libs=corelib network widgets gui plugins testlib
-$(package)_patches=fix_qt_pkgconfig.patch mac-qmake.conf fix_configure_mac.patch fix_no_printer.patch
+$(package)_patches=fix_qt_pkgconfig.patch mac-qmake.conf fix_configure_mac.patch fix_no_printer.patch fix_rcc_determinism.patch
 
 $(package)_qttranslations_file_name=qttranslations-$($(package)_suffix)
 $(package)_qttranslations_sha256_hash=9822084f8e2d2939ba39f4af4c0c2320e45d5996762a9423f833055607604ed8
@@ -94,6 +94,7 @@ $(package)_config_opts_i686_linux  = -xplatform linux-g++-32
 $(package)_config_opts_x86_64_linux = -xplatform linux-g++-64
 $(package)_config_opts_mingw32  = -no-opengl -xplatform win32-g++ -device-option CROSS_COMPILE="$(host)-"
 $(package)_build_env  = QT_RCC_TEST=1
+$(package)_build_env += QT_RCC_SOURCE_DATE_OVERRIDE=1
 endef
 
 define $(package)_fetch_cmds
@@ -133,6 +134,7 @@ define $(package)_preprocess_cmds
   patch -p1 -i $($(package)_patch_dir)/fix_qt_pkgconfig.patch &&\
   patch -p1 -i $($(package)_patch_dir)/fix_configure_mac.patch &&\
   patch -p1 -i $($(package)_patch_dir)/fix_no_printer.patch &&\
+  patch -p1 -i $($(package)_patch_dir)/fix_rcc_determinism.patch &&\
   echo "!host_build: QMAKE_CFLAGS     += $($(package)_cflags) $($(package)_cppflags)" >> qtbase/mkspecs/common/gcc-base.conf && \
   echo "!host_build: QMAKE_CXXFLAGS   += $($(package)_cxxflags) $($(package)_cppflags)" >> qtbase/mkspecs/common/gcc-base.conf && \
   echo "!host_build: QMAKE_LFLAGS     += $($(package)_ldflags)" >> qtbase/mkspecs/common/gcc-base.conf && \