debian/rules: Stop manually handling multiarch; cmake works correctly now

debian/rules

@@ -13,15 +13,11 @@ export DEB_BUILD_MAINT_OPTIONS = hardening=+all
 
 export DPKG_GENSYMBOLS_CHECK_LEVEL = 4
 
-# DEB_* variables
-DEB_HOST_MULTIARCH ?= $(shell dpkg-architecture -qDEB_HOST_MULTIARCH)
-
 # disable gtk stuff to minimize Build-Depends
 CONFIGURE_ARGS :=				\
 	-DCMAKE_BUILD_TYPE=Release		\
 	-DCMAKE_C_FLAGS_RELEASE="$(CFLAGS)"	\
 	-DCMAKE_CXX_FLAGS_RELEASE="$(CXXFLAGS)"	\
-	-DCMAKE_INSTALL_LIBDIR="lib/$(DEB_HOST_MULTIARCH)" \
 	-DENABLE_GLIB=ON			\
 	-DENABLE_QT5=ON				\
 	-DENABLE_CPP=ON				\