bug 15000: aspect/aspectMask inconsistencies (WIP)

Rename all aspect to aspectMask.

https://cvs.khronos.org/bugzilla/show_bug.cgi?id=15000
diff --git a/demos/cube.c b/demos/cube.c
index aff26b0..f837589 100644
--- a/demos/cube.c
+++ b/demos/cube.c
@@ -1075,7 +1075,7 @@
 
     if (required_props & VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT) {
         const VkImageSubresource subres = {
-            .aspect = VK_IMAGE_ASPECT_COLOR_BIT,
+            .aspectMask = VK_IMAGE_ASPECT_COLOR_BIT,
             .mipLevel = 0,
             .arrayLayer = 0,
         };