guix: Drop non-existent directories

Author: hebasto

contrib/guix/libexec/build.sh

@@ -69,7 +69,7 @@ unset CPLUS_INCLUDE_PATH
 unset OBJC_INCLUDE_PATH
 unset OBJCPLUS_INCLUDE_PATH
 
-export LIBRARY_PATH="${NATIVE_GCC}/lib:${NATIVE_GCC}/lib64:${NATIVE_GCC_STATIC}/lib:${NATIVE_GCC_STATIC}/lib64"
+export LIBRARY_PATH="${NATIVE_GCC}/lib:${NATIVE_GCC_STATIC}/lib"
 export C_INCLUDE_PATH="${NATIVE_GCC}/include"
 export CPLUS_INCLUDE_PATH="${NATIVE_GCC}/include/c++:${NATIVE_GCC}/include"
 export OBJC_INCLUDE_PATH="${NATIVE_GCC}/include"