[cmake] fix nx_tzdb msvc link error (tmp) (#356)

This is an incredibly stupid and nonsensical bug that I have no way of possibly explaining. This is a temporary workaround until I can reproduce it and figure it out.

Otherwise MSVC linker crashes during final link phase. thanks microsoft

Signed-off-by: crueter <crueter@crueter.xyz>
Reviewed-on: #356
Reviewed-by: Shinmegumi <shinmegumi@eden-emu.dev>
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Co-authored-by: crueter <crueter@crueter.xyz>
Co-committed-by: crueter <crueter@crueter.xyz>

src/common/ring_buffer.h

@@ -15,6 +15,7 @@
 #include <span>
 #include <type_traits>
 #include <vector>
+#include <mutex>
 
 namespace Common {