Merge pull request RPCS3#1511 from vlj/d3d12

D3d12: Tweaks

Merge pull request RPCS3#1514 from kd-11/gl_attrib_fix

gl: Minor fixes and improvements

Merge pull request RPCS3#1481 from tambry/racoon

Implement _sys_memmove, minor fixes

Merge pull request RPCS3#1512 from kd-11/gl_sampler_fix

gl: Always bind null for unused shader inputs

Merge pull request RPCS3#1516 from kd-11/rsx_textureutils_fix

Handle swizzled CELL_GCM_B8 textures

Merge pull request RPCS3#1510 from vlj/rsx

rsx/common/d3d12/gl: Use span in vertex upload function.

Merge pull request RPCS3#1509 from vlj/rsx

rsx/common: Track transform constant update.

Merge pull request RPCS3#1508 from vlj/d3d12

D3d12: Tweak root signature and improves HRESULT message

Merge pull request RPCS3#1507 from vlj/vulkan

Vulkan: Add glslang and LoaderAndValidationLayers

Merge pull request RPCS3#1502 from kd-11/gl_staging

gl: Enable texture and render target caching for OpenGL