merge some mGBA upstream commits, partially revert c891cc2cb5 (upstream commits makes our changes not really needed)

src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.cs

@@ -40,7 +40,9 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 				rom,
 				rom.Length,
 				ref overrides,
-				skipBios: _syncSettings.SkipBios);
+				skipBios: _syncSettings.SkipBios && !lp.DeterministicEmulationRequested);
+
+			// the core might ignore our request to run the bios intro if the game cannot boot with the bios intro: that's okay
 
 			if (Core == IntPtr.Zero)
 			{

submodules/mgba

@@ -1 +1 @@
-Subproject commit f59c9650fd141fd68a9b3f51f7860bb3791aa193
+Subproject commit 26ea5311797656a87ebfcabd55fe295a15e55535