* Update release number to 121.
Github Issues:
* Add missing `structextends` attribute in `vk.xml` for
slink:VkPhysicalDevicePipelineExecutablePropertiesFeaturesKHR (public
issue 1018).
* Change attributes of flink:vkCmdCopyAccelerationStructureNV,
flink:vkCmdWriteAccelerationStructuresPropertiesNV,
flink:vkCmdBuildAccelerationStructureNV, and flink:vkCmdTraceRaysNV to
require that these commands execute outside renderpasses (public issue
1021).
* Add an issue to the `<<VK_EXT_buffer_device_address>>` appendix
discussing the introduction of new names and aliasing by equivalent old
names (public pull request 1024).
Internal Issues:
* Protect the `VK_KHR_sampler_mirror_clamp_to_edge` extension with
asciidoctor conditionals, and remove it from the core-only specification
builds, where it had previously been force-included in the Makefile. It
is now treated like any other extension (internal issue 1776).
* Edit some asciidoctor anchor names starting with `features-features-` to
just start with `features-`, since the old chapters was split into 3
pieces. There are still some mild naming inconsistencies with anchors
which may be addressed in the future (internal issue 1792).
* Add `KHR` alias for the non-suffixed extension token
ename:VK_SAMPLER_ADDRESS_MODE_MIRROR_CLAMP_TO_EDGE, for compatibility
with naming rules for extensions (internal issue 1796).
* Clarify requirements for external memory in NOTEs for
sname:VkExternalMemoryBufferCreateInfo, and valid usage statements for
flink:vkBindBufferMemory, slink:VkBindBufferMemoryInfo,
flink:vkBindImageMemory, and slink:VkBindImageMemoryInfo (internal merge
request 3301).
* Make extension version numbers in `vk.xml` and extension appendices
consistent. In a few cases, we could not recover history at this
granularity, and left the summary of a version's change undefined
(internal merge request 3323).
* Fix invocation of `CodeInlineMacro` in the Ruby extension backing the
`code:` macro, which was delegating to the wrong base class (internal
merge request 3331).
* Modify `reg.py` to do a better job of recognizing equivalent <enum>
definitions.
* Add a `sortorder` attribute to XML feature and extension tags.
New Extensions
* `<<VK_AMD_device_coherent_memory>>`
