loader: Trampoline vkEnumeratePhysDev should use layer-returned physDev count

Modify the trampoline vkEnumeratePhysicalDevices() implementation to
enumerate the number of physical devices based on what the top-most
layer reports and not what the terminator_EnumeratePhysicalDevices
counted. This allows intermediate layers to modify the physical device
count.

Change-Id: Ifd5c3c8c4db53cf97b976feefe18de7cfef47e35
1 file changed