Core: ClampRangeSize fixes (#3555)

* Swap !IsFree() for IsMapped()

IsFree only checks if the VMAType == Free. As is, that means ClampRangeSize will include memory that is Reserved or PoolReserved, and neither of those types are GPU mapped.

This fixes this bug, may help with some non-GPU memory asserts.

* Apply ClampRangeSize to vertex buffers

Helps with some cases encountered by UE and Minecraft.

src/core/memory.cpp

@@ -82,7 +82,7 @@ u64 MemoryManager::ClampRangeSize(VAddr virtual_addr, u64 size) {
     ++vma;
 
     // Keep adding to the size while there is contigious virtual address space.
-    while (!vma->second.IsFree() && clamped_size < size) {
+    while (vma->second.IsMapped() && clamped_size < size) {
         clamped_size += vma->second.size;
         ++vma;
     }