doc/go1.17: document new debug/elf constant

For #39677
For #44513

Change-Id: I8c4193fd4359b83e6739e7e30a3a42b5f21b0f1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/323275
Trust: Ian Lance Taylor <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: ianlancetaylor

doc/go1.17.html

@@ -373,6 +373,15 @@ <h3 id="minor_library_changes">Minor changes to the library</h3>
   </dd>
 </dl><!-- database/sql -->
 
+<dl id="debug/elf"><dt><a href="/pkg/debug/elf/">debug/elf</a></dt>
+  <dd>
+    <p><!-- CL 239217 -->
+      The <a href="/pkg/debug/elf/#SHT_MIPS_ABIFLAGS"><code>SHT_MIPS_ABIFLAGS</code></a>
+      constant has been added.
+    </p>
+  </dd>
+</dl><!-- debug/elf -->
+
 <dl id="encoding/binary"><dt><a href="/pkg/encoding/binary/">encoding/binary</a></dt>
   <dd>
     <p><!-- CL 299531 -->