Change name of update to Makefile.release

Per #487 (comment)

Author: oddhack

Makefile renamed to Makefile.release

@@ -1,8 +1,8 @@
 # Copyright 2024 The Khronos Group Inc.
 # SPDX-License-Identifier: Apache-2.0
 
-# Makefile to update external files generated in other repositories when
-# a public specification update is done.
+# Makefile.release - update external files generated in Vulkan spec
+# repository when a public specification update is done.
 
 # Needed to get the right version of test, apparently
 SHELL  = /bin/bash
@@ -15,13 +15,13 @@ SPEC	 = $(GIT)/Vulkan-Docs
 HPP	 = $(GIT)/Vulkan-Hpp
 REGISTRY = $(GIT)/registry/vulkan
 
-update: consistency-check create-branch update-files push-branch
+update: version-check create-branch update-files push-branch
 
 # Working branch for the update, and a test if it exists
 BRANCH = update-$(REVISION)
 
 # Switch to new branch which will contain the update
-create-branch: consistency-check
+create-branch: version-check
 	git switch -q main
 	git pull -q
 	# If branch already exists, do nothing
@@ -55,7 +55,7 @@ update-headers:
 	cp -r $(HPP)/vulkan/* include/vulkan/
 	rm -f $(SCHPPFILES)
 
-# Top-level scripts / XML
+# Top-level scripts / XML to install
 SCRIPTS = \
     $(SPEC)/scripts/cgenerator.py \
     $(SPEC)/scripts/generator.py \
@@ -68,12 +68,12 @@ SCRIPTS = \
     $(SPEC)/xml/video.xml \
     $(REGISTRY)/specs/1.3-extensions/validation/validusage.json
 
-# Scripts in registry/spec_tools
+# Scripts in registry/spec_tools to install
 SCRIPT_TOOLS = \
     $(SPEC)/scripts/spec_tools/conventions.py \
     $(SPEC)/scripts/spec_tools/util.py
 
-# Profiles
+# Profiles to install
 PROFILES = \
     $(wildcard $(SPEC)/xml/profiles/*)
 
@@ -104,5 +104,5 @@ push-branch:
 	@echo git push --set-upstream origin $(BRANCH)
 	@echo git switch main
 
-consistency-check:
+version-check:
 	@if test $(REVISION) = 999 ; then echo "Must specify explicit REVISION= in make invocation" ; exit 1 ; fi