Slight polish to DMA (#1856)

* Slight polish to DMA

- Default-initialize members explicitly
- Mark some methods as const noexcept
- Initialize DMA::MRAMBurstTable to DMATiming::MRAMDummy
- Use the default destructor

* Move DMA_Timings definitions to a source file

- To ensure constant and unique addresses

* Include some extra DMA members in the savestate

* Simplify serializing the DMA table

- Extend the dummy table to 256 bytes (same length as the real ones)

* Revert the type change to DMA::DoSavestate

* Keep the MRAMBurstTable inside the DMA class, instead of using a pointer

- If we use a pointer to an external table, then we can't use it in savestates (else that external table gets overwritten)

src/DMA.cpp

@@ -47,21 +47,16 @@ using Platform::LogLevel;
 // TODO: timings are nonseq when address is fixed/decrementing
 
 
-DMA::DMA(u32 cpu, u32 num)
+DMA::DMA(u32 cpu, u32 num) :
+    CPU(cpu),
+    Num(num)
 {
-    CPU = cpu;
-    Num = num;
-
     if (cpu == 0)
         CountMask = 0x001FFFFF;
     else
         CountMask = (num==3 ? 0x0000FFFF : 0x00003FFF);
 }
 
-DMA::~DMA()
-{
-}
-
 void DMA::Reset()
 {
     SrcAddr = 0;
@@ -82,6 +77,7 @@ void DMA::Reset()
     Executing = false;
     InProgress = false;
     MRAMBurstCount = 0;
+    MRAMBurstTable = DMATiming::MRAMDummy;
 }
 
 void DMA::DoSavestate(Savestate* file)
@@ -106,6 +102,10 @@ void DMA::DoSavestate(Savestate* file)
     file->Bool32(&InProgress);
     file->Bool32(&IsGXFIFODMA);
     file->Var32(&MRAMBurstCount);
+    file->Bool32(&Executing);
+    file->Bool32(&Stall);
+
+    file->VarArray(MRAMBurstTable.data(), sizeof(MRAMBurstTable));
 }
 
 void DMA::WriteCnt(u32 val)