move fixup_f4 to unicodedomino_compat.def

(it’s a fully-merged bugfix so it fits)

unicodedomino.sty

@@ -44,9 +44,6 @@
 \ifx\UTFviii@decode\@undefined%
  \input{unicodedomino_kernel_better_decode.def}%
 \fi%
-\ifx\UTFviii@hexcodepoint\@undefined%
- \input{unicodedomino_kernel_fixup_f4.def}%
-\fi%
 \input{unicodedomino_kernel_cosmetics.def}%
 
 % retrieve the last octet

unicodedomino_compat.def

@@ -36,6 +36,8 @@
 
 % added in v1.2e 2018/09/28
 \ifx\UTFviii@hexcodepoint\@undefined%
+ % monkey-patch bugfixes
+ \input{unicodedomino_kernel_fixup_f4.def}%
  % override message to format the codepoint correctly
  \gdef\UTFviii@splitcsname#1:#2\relax{%
   #2 (\expandafter\UTFviii@hexcodepoint\expandafter{%