demos: Fix static analysis warnings in vulkaninfo
demos: Fix static analysis warnings in vulkaninfo

Add exit code after failed mallocs.
Dynamically allocate gpu info and handle arrays, getting
rid of artificial limit.  This also moves a large allocation
from the stack to the heap.
There are still some false positives from the MSFT analyzer
that aren't worth fixing or suppressing.

KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools