Following the previous commit (8fb8b35552738814a6bd10a9c1c2a0d3b3e2dc0f),
and since all "real" input arguments are later funneled through
ldfile_try_open_bfd(), performing the name-substitution during the
input statement list construction phase is no longer necessary.
Following this commit, image arguments (e.g. libfoo.so) are replaced with
temporary mdso import libraries that are generated on the fly using the
perk and mdso library interfaces.
As should be noted, the above logic is only in effect when PE_TARGET_MDSO
is defined. For non-mdso targets (e.g. mingw), ld continues to generate
in-memory legacy .idata import libraries as it did before.
