sysgpu: prevent smaller memory types from selected (#1445)

Only taking a look at the bitflags for linear_map_readable
caused memory indexes with a smaller heap space to be selected.

Signed-off-by: Shail Patel <shailpatel67@gmail.com>

Author: shailpatels

src/sysgpu/vulkan.zig

@@ -3558,7 +3558,19 @@ const MemoryAllocator = struct {
             const heap_size = mem_heaps[mem_type.heap_index].size;
             const candidate = switch (mem_kind) {
                 .lazily_allocated => flags.lazily_allocated_bit,
-                .linear_write_mappable => flags.host_visible_bit and flags.host_coherent_bit and !flags.device_coherent_bit_amd,
+                .linear_write_mappable => blk: {
+                    if (flags.host_visible_bit and flags.host_coherent_bit and !flags.device_coherent_bit_amd) {
+                        if (best_type) |best| {
+                            const best_heap_size = mem_heaps[mem_types[best].heap_index].size;
+                            if (heap_size > best_heap_size) {
+                                break :blk true;
+                            }
+                            break :blk false;
+                        }
+                        break :blk true;
+                    }
+                    break :blk false;
+                },
                 .linear_read_mappable => blk: {
                     if (flags.host_visible_bit and flags.host_coherent_bit and !flags.device_coherent_bit_amd) {
                         if (best_type) |best| {
@@ -3584,7 +3596,7 @@ const MemoryAllocator = struct {
                         if (mem_types[best].property_flags.device_local_bit) {
                             if (flags.device_local_bit and !flags.device_coherent_bit_amd) {
                                 const best_heap_size = mem_heaps[mem_types[best].heap_index].size;
-                                if (heap_size > best_heap_size or flags.host_visible_bit) {
+                                if (heap_size > best_heap_size) {
                                     break :blk true;
                                 }
                             }