deprecation: add the md to documentation Makefile

Originally deprecation.md was pulled verbatim to
the built documentation. This resulted in very
weird paths on the spdk.io:
https://spdk.io/doc/md__home_sys_sgsw_oss_spdk_github_io_spdk_deprecation.html#deprecation

Use the way that changelog does it, by copying
the file and adding appropriate section links.

Now only the Doxygen version will contain the
section links. Meanwhile deprecation.md in
project root will not. This improves readability.

Change-Id: Ic5c1caf7603b847b3c7445bde76e277ba1ccb740
Signed-off-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/16574
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>

deprecation.md

@@ -1,6 +1,6 @@
 # Deprecation
 
-## ABI and API Deprecation {#deprecation}
+## ABI and API Deprecation
 
 This document details the policy for maintaining stability of SPDK ABI and API.
 
@@ -17,7 +17,7 @@ Deprecated code paths must be registered with `SPDK_DEPRECATION_REGISTER()` and
 log at the warn level when `SPDK_LOG_DEPRECATED()` is called, subject to rate limits.
 The tags can be matched with the level 4 headers below.
 
-## Deprecation Notices {#deprecation-notices}
+## Deprecation Notices
 
 ### PMDK
 

doc/.gitignore

@@ -1,3 +1,4 @@
-# changelog.md is generated by Makefile
+# changelog.md and deprecation.md is generated by Makefile
 changelog.md
+deprecation.md
 output/

doc/Doxyfile

@@ -813,7 +813,7 @@ INPUT                  += \
                          compression.md \
                          concurrency.md \
                          containers.md \
-                         ../deprecation.md \
+                         deprecation.md \
                          distributions.md \
                          event.md \
                          ftl.md \

doc/Makefile

@@ -13,6 +13,10 @@ all: doc
 
 doc: output
 
+deprecation.md: ../deprecation.md
+	$(Q)sed -e 's/^# Deprecation/# Deprecation {#deprecation}/' \
+	    < $< > $@
+
 changelog.md: ../CHANGELOG.md
 	$(Q)sed -e 's/^# Changelog/# Changelog {#changelog}/' \
 	    -e 's/^##/#/' \
@@ -20,9 +24,9 @@ changelog.md: ../CHANGELOG.md
 	    -e '/# v..\...:/s/\./-/2' \
 	    < $< > $@
 
-output: Doxyfile changelog.md $(wildcard *.md) $(wildcard ../include/spdk/*.h)
+output: Doxyfile changelog.md deprecation.md $(wildcard *.md) $(wildcard ../include/spdk/*.h)
 	$(Q)rm -rf $@
 	$(Q)doxygen Doxyfile
 
 clean:
-	$(Q)rm -rf output changelog.md
+	$(Q)rm -rf output changelog.md deprecation.md