Remove libcxx stub library and move operator new to mammoth.

sys/denali/CMakeLists.txt

@@ -12,7 +12,6 @@ target_include_directories(denali
    "${CMAKE_CURRENT_SOURCE_DIR}/include")
 
 target_link_libraries(denali
-  cxx
   glacier
   mammoth_lib
   yellowstonestub

sys/yellowstone/CMakeLists.txt

@@ -8,7 +8,6 @@ add_executable(yellowstone
    PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 
 target_link_libraries(yellowstone
-  cxx
   mammoth_lib
   glacier
   libdenali

sys/yellowstone/yellowstone_server.cpp

@@ -8,8 +8,6 @@
 #include "hw/gpt.h"
 #include "include/yellowstone.h"
 
-// FIXME: This linkage was missing :(
-void* operator new[](uint64_t size) { return malloc(size); }
 namespace {
 
 void ServerThreadBootstrap(void* yellowstone) {