add a hack so that codegen doesn't abort on missing sema of initializers, now

we emit stuff like this:

abort on missing sema of initializers, now
we emit stuff like this:

t3.c:1:24: warning: cannot codegen this initializer yet
const char x[2][4] = { { 'a', 'b', '\0', '\0' }, { 'c', 'd', 'e', '\0' } };
                       ^~~~~~~~~~~~~~~~~~~~~~~~

This should be removed when sema is finished.

llvm-svn: 45086