LaTeX: avoid "The remreset package is obsolete" warnings in latex log

sphinx/texinputs/sphinx.sty

@@ -183,7 +183,10 @@
 % control caption around literal-block
 \RequirePackage{capt-of}
 \RequirePackage{needspace}
-\RequirePackage{remreset}% provides \@removefromreset
+% LaTeX 2018-04-01 and later provides \@removefromreset
+\ltx@ifundefined{@removefromreset}
+    {\RequirePackage{remreset}}
+    {}% avoid warning
 % to make pdf with correct encoded bookmarks in Japanese
 % this should precede the hyperref package
 \ifx\kanjiskip\@undefined