Add the Denali disk driver.

Begin enumerating information from the PCI structure and HBA AHCI
structures.

Currently the PCI structure address is hardcoded but it should be
passed via a capability from the init process in the future.

sys/CMakeLists.txt

@@ -1,16 +1,5 @@
 set(CMAKE_SHARED_LIBRARY_LINK_CXX_FLAGS "")
 
 add_subdirectory(yellowstone)
+add_subdirectory(denali)
 
-add_executable(test2
-  test2.cpp)
-
-target_link_libraries(test2
-  cxx
-  mammoth_lib)
-
-set_target_properties(test2
-  PROPERTIES
-  COMPILE_FLAGS "${CMAKE_CXX_FLAGS} ${BASE_COMPILE_FLAGS}"
-  LINK_FLAGS "${CMAKE_EXE_LINK_FLAGS} ${BASE_LINK_FLAGS}"
-  )