Drop the parts that are being dropped.
Move the things that are being moved.
Also move the verilog stuff out of README and into the docs.
GettingStarted is less cut and dry, so hold off on that one.
- Remove unused statics CONST_FALSE and CONST_TRUE (which appear to have been folded into the `Index` declaration as CFALSE and CTRUE).
- Assign default value of EMPTY_LIT to `a` and `b` for comparison ops.
- Tag debug only variables with YS_MAYBE_UNUSED, don't assign unused variables (but continue to call the function because it moves the file pointer).
Avoid error:
```
kernel/mem.cc:1683:7: error: conflicting declaration ‘using addr_t = using addr_t = uint32_t’
1683 | using addr_t = MemContents::addr_t;
| ^~~~~~
In file included from /usr/include/sys/types.h:222,
from /usr/include/pthread.h:11,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/x86_64-pc-cygwin/bits/gthr-default.h:35,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/x86_64-pc-cygwin/bits/gthr.h:148,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/ext/atomicity.h:35,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/bits/cow_string.h:37,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/bits/basic_string.h:51,
from /usr/lib/gcc/x86_64-pc-cygwin/12/include/c++/string:53,
from ./kernel/yosys_common.h:27,
from ./kernel/yosys.h:42,
from ./kernel/mem.h:23,
from kernel/mem.cc:20:
/usr/include/machine/types.h:63:15: note: previous declaration as ‘typedef char* addr_t’
63 | typedef char *addr_t;
```
According to IntelliSense, only the return types need to be prefixed with `MemContents::`, the rest are automagically using the class definition and highlight as `using Yosys::MemContents::addr_t = uint32_t`.
`Const::size()` returns int, so change iterators that use it to `auto` instead of `size_t`.
For cases where size is being explicitly cast to `int`, use the wrapper that we already have instead: `Yosys::GetSize()`.
