Results: Implement namespaced, type-safe results.

Because I was working on multiple things at once, this commit also:
- Adds wrappers for/linker flags to wrap CXX exceptions to make them
  abort. This saves ~0x8000 of memory in every system module.
- Broadly replaces lines of the pattern if (cond) { return ResultX; }
  with R_UNLESS(!cond, ResultX());.
- Reworks the R_TRY_CATCH macros (and the result macros in general).

stratosphere/libstratosphere/source/dd/dd_io_mappings.cpp

@@ -24,7 +24,7 @@ namespace sts::dd {
         const u64 aligned_size = size + offset;
         R_TRY_CATCH(svcQueryIoMapping(&virtual_addr, aligned_addr, aligned_size)) {
             /* Official software handles this by returning 0. */
-            R_CATCH(ResultKernelNotFound) { return 0; }
+            R_CATCH(svc::ResultNotFound) { return 0; }
         } R_END_TRY_CATCH_WITH_ASSERT;
 
         return static_cast<uintptr_t>(virtual_addr + offset);