Use liarc built-in objects only for LOAD, not for FASLOAD. When we're

Use liarc built-in objects only for LOAD, not for FASLOAD.  When we're
actually loading code for execution, we need them; when we're loading
code for data (e.g., when loading scode for the compiler -- especially
when it is compiling itself, or other parts of the system that are
loaded into the compiler image), we need the file and not the compiled
expression statically linked into the microcode.

This is a kludge, but it is necessary for bootstrapping liarc.  I
don't know whether there is any code that relies on FASLOAD yielding
built-in objects, however; I suspect not.