Remove the last ConfigEntry state (#1902)

* Get rid of `ConfigEntry::ExternalBIOSEnable`

- Now the BIOS files themselves are checked
- The frontend's `Config::ExternalBIOSEnable` is not affected

* Add `JITArgs`

* Pass the JIT status to the `ARM` constructors

* Encapsulate `NDS::EnableJIT`

* Pass `JITArgs` to `ARMJIT`'s constructor

* Remove the `JIT_*` `ConfigEntry`s in favor of members

- Allow all the JIT args to be set with `NDS::SetJITArgs`
- Encapsulate the JIT-related parameters in `ARMJIT` so they can reset the block cache if changed
- Update the active (or newly-created) console in the frontend with adjusted JIT args

* Make audio bit depth and interpolation configurable in `NDSArgs`

- Define enums for both
- Give those settings default values in `NDSArgs`
- Remove `ConfigEntry::AudioBitDepth`
- Initialize these settings in the relevant SPU constructors

* Move the last DSi-specific logic in `Reset` to its own subclass

* Remove `ConfigEntry::DSi_FullBIOSBoot`

- Add members to `DSi` instead for getting and setting this
- Update the frontend to accommodate these changes

* Oops, missed a spot

* Remove `ConfigEntry::Firm_MAC` and `Platform::GetConfigArray`

- Also move the MAC parsing code to `ROMManager`

* Remove the last `ConfigEntry` state

- Make GDB support configurable via members

* Add some `#ifdef`s that I'd almost forgotten

src/DSi.h

@@ -172,7 +172,10 @@ public:
     u8 GPIO_IE;
     u8 GPIO_WiFi;
 
+    bool GetFullBIOSBoot() const noexcept { return FullBIOSBoot; }
+    void SetFullBIOSBoot(bool full) noexcept { FullBIOSBoot = full; }
 private:
+    bool FullBIOSBoot;
     void Set_SCFG_Clock9(u16 val);
     void Set_SCFG_MC(u32 val);
     void DecryptModcryptArea(u32 offset, u32 size, u8* iv);