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;
     }

src/video_core/buffer_cache/buffer_cache.cpp

@@ -283,7 +283,8 @@ void BufferCache::BindVertexBuffers(const Vulkan::GraphicsPipeline& pipeline) {
 
     // Map buffers for merged ranges
     for (auto& range : ranges_merged) {
-        const auto [buffer, offset] = ObtainBuffer(range.base_address, range.GetSize(), false);
+        const u64 size = memory->ClampRangeSize(range.base_address, range.GetSize());
+        const auto [buffer, offset] = ObtainBuffer(range.base_address, size, false);
         range.vk_buffer = buffer->buffer;
         range.offset = offset;
     }