Use --nosync during make check's initdb call.

We left this out of commit b966dd6c
so as to get some more buildfarm testing of the new fsync code in initdb.
But since no problems have turned up, it's probably time to save the
cycles.

src/test/regress/pg_regress.c

@@ -2150,7 +2150,7 @@ regression_main(int argc, char *argv[], init_function ifunc, test_function tfunc
 		/* initdb */
 		header(_("initializing database system"));
 		snprintf(buf, sizeof(buf),
-				 SYSTEMQUOTE "\"%s/initdb\" -D \"%s/data\" -L \"%s\" --noclean%s%s > \"%s/log/initdb.log\" 2>&1" SYSTEMQUOTE,
+				 SYSTEMQUOTE "\"%s/initdb\" -D \"%s/data\" -L \"%s\" --noclean --nosync%s%s > \"%s/log/initdb.log\" 2>&1" SYSTEMQUOTE,
 				 bindir, temp_install, datadir,
 				 debug ? " --debug" : "",
 				 nolocale ? " --no-locale" : "",