Resync optick with my latest changes submitted to head stream

[SRSaunders]

This PR brings optick up-to-date with my changes submitted to the head stream in PR bombomby/optick#196:

1. Vulkan: Enables vkResetQueryPoolEXT as fallback if vkResetQueryPool is not available in the driver via the Vulkan 1.2 hostQueryReset feature. This change adds support for non-Vulkan 1.2 applications via the VK_EXT_host_query_reset extension. Also adds error detection and reporting if either of these capabilites are not enabled. Note RBDoom3BFG is a Vulkan 1.2 application that uses the hostQueryReset feature and thus this change is transparent to the game.
2. Vulkan: Discovers and assigns dynamic Vulkan functions separately for each device/node vs. assigning them globally. Static and manually assigned Vulkan functions remain global across devices/nodes. This is a correctness and optimization change for multi-GPU setups using dynamic functions, which is applicable to RBDoom3BFG.
3. Vulkan: Cleaned up naming and usage of node and payload in optick_gpu.vulkan.cpp for consistency.
4. Common: Simplified error code when UNICODE is enabled on Windows. Uses the TEXT() macro vs explicit defines.

[RobertBeckebans]

I only checked if this compiled on Windows and I trust you on the rest.

[RobertBeckebans]

@SRSaunders I would be nice if you could check the current master if that still compiles for you. There is a new rbdmap executable mainly built and separated from the rest of the engine using the DMAP compile flag. Some people requested a separate oldschool map compiler so they don't have to open the engine every time they compile a map and just hit a button in TrenchBroomBFG. The merged branch also dumps a lot of legacy image loading code like the JPG and PNG libraries and replaces those with STB image header only libs like it is handled in the dhewm3 source port.

[SRSaunders]

Thanks for the heads up. Tested and found one small compile failure on macOS, plus a few minor clean-ups.

PR #903 submitted with suggested changes.