Fixes crash that occurs in applications that use both GL and Vulkan,
Like UE5 Vulkan native games. Fixes Ender Magnolia.
The issue here is that UE5 loads libGL first, which initializes our
libGL thunks, setting its X11Manager's functions.
It then loads libvulkan, which calls our oninit constructor, which
because of the symbol conflict, calls in to the libGL thunk's host
functions to reinitialize its function pointers, never initializing the
Vulkan X11Manager's functions. It would then crash as soon as an X11
function was used.
Give them unique symbol names so we don't accidentally look up the
incorrect symbol.
Justin Becker