venus: add extensions tangled with EDS3

What does this MR do and why?

venus: add extensions tangled with EDS3

Related MRs:

• renderer: virgl/virglrenderer!1468 (merged)
• protocol: virgl/venus-protocol!92 (merged)

There're dynamic state and cmds from EDS3 that should be gated upon below extensions:

• VK_EXT_blend_operation_advanced
• VK_EXT_sample_locations

However, the spec registry at that time accidentally missed such info (except the cmds related to NV extensions). As a result, venus-protocol has baked in those cmds solely based on the EDS3 support from the renderer side. If we uprev the spec registry, cmds from the above 2 extensions will be dropped from venus cmd serialization, breaking the driver<->renderer compatibility. So...though not trivial, it's better to get those extensions properly supported via venus.

This MR also fixes a bug in the maint5 support.

TEST:

• dEQP-VK.pipeline.*.multisample.sample_locations_ext.*

/cc