all host_applications: remove non-existent projects

The ALL_APPS symbol will optionally build an additional set of projects,
however, two of them don't exist anymore. Remove them from the list of
ALL_APPS.

Signed-off-by: Trevor Woerner <twoerner@gmail.com>

host_applications/linux/CMakeLists.txt

@@ -15,8 +15,6 @@ add_subdirectory(apps/dtmerge)
 
 if(ALL_APPS)
  add_subdirectory(apps/vcdbg)
- add_subdirectory(libs/elftoolchain)
- # add_subdirectory(apps/smct)
  add_subdirectory(apps/edid_parser)
  add_subdirectory(apps/hello_pi)
 endif()