Actually fix the substitution this time

configure.ac

@@ -49,7 +49,6 @@ if [[ "$PYTHON_EXEC_PREFIX" != "$PYTHON_PREFIX" ]]; then
 fi
 PYTHON_LIBS="$PYTHON_LIBS -lpython${PYTHON_VERSION}${PYTHON_ABIFLAGS}"
 
-AC_SUBST(PYTHON)
 AC_SUBST(PYTHON_CFLAGS)
 AC_SUBST(PYTHON_LDFLAGS)
 AC_SUBST(PYTHON_LIBS)

src/Makefile.am

@@ -12,7 +12,9 @@ EXTRA_DIST = \
 	frida-trace.in \
 	frida-repl.in
 
-do_substitution = sed -e 's,[@]pythondir[@],$(pythondir),g' \
+do_substitution = sed \
+	-e 's,[@]PYTHON[@],$(PYTHON),g' \
+	-e 's,[@]pythondir[@],$(pythondir),g' \
 	-e 's,[@]PACKAGE[@],$(PACKAGE),g' \
 	-e 's,[@]VERSION[@],$(VERSION),g'