Move import to a windows specific file

examples/all/all_vendor.odin

@@ -20,7 +20,6 @@ import MIX        "vendor:sdl2/mixer"
 import TTF        "vendor:sdl2/ttf"
 
 import vk         "vendor:vulkan"
-import wgpu       "vendor:wgpu"
 
 // NOTE(bill): only one can be checked at a time
 import lua_5_4    "vendor:lua/5.4"
@@ -51,7 +50,6 @@ _ :: MIX
 _ :: TTF
 
 _ :: vk
-_ :: wgpu
 
 _ :: lua_5_4
 

examples/all/all_vendor_windows.odin

@@ -0,0 +1,4 @@
+package all
+
+import wgpu "vendor:wgpu"
+_ :: wgpu