[cmake] Cleanup dynarmic's CMake (#4365)

Removes a handful of unused/untested features (like disabling CPU detection)
and brings the CMake of dynarmic more in line with the rest of the build system.

Signed-off-by: lizzie <lizzie@eden-emu.dev>

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4365
Reviewed-by: crueter <crueter@eden-emu.dev>

src/dynarmic/tests/CMakeLists.txt

@@ -1,7 +1,5 @@
 # SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 # SPDX-License-Identifier: GPL-3.0-or-later
-include(TargetArchitectureSpecificSources)
-
 add_executable(dynarmic_tests
     fp/FPToFixed.cpp
     fp/FPValue.cpp
@@ -44,13 +42,13 @@ if (DYNARMIC_TESTS_USE_UNICORN)
     )
 endif()
 
-if ("riscv" IN_LIST ARCHITECTURE)
+if (ARCHITECTURE_riscv64)
     target_link_libraries(dynarmic_tests PRIVATE biscuit::biscuit)
 endif()
 
-if ("x86_64" IN_LIST ARCHITECTURE)
+if (ARCHITECTURE_x86_64)
     target_link_libraries(dynarmic_tests PRIVATE xbyak::xbyak)
-    target_architecture_specific_sources(dynarmic_tests "x86_64"
+    target_sources(dynarmic_tests PRIVATE
         x64_cpu_info.cpp
         native/preserve_xmm.cpp
     )