patch 8.2.5057: using gettimeofday() for timeout is very inefficient

Problem:    Using gettimeofday() for timeout is very inefficient.
Solution:   Set a platform dependent timer. (Paul Ollis, closes #10505)
diff --git a/src/regexp.h b/src/regexp.h
index 304c82d..89c41c9 100644
--- a/src/regexp.h
+++ b/src/regexp.h
@@ -173,7 +173,7 @@
     // bt_regexec_nl or nfa_regexec_nl
     int		(*regexec_nl)(regmatch_T *, char_u *, colnr_T, int);
     // bt_regexec_mult or nfa_regexec_mult
-    long	(*regexec_multi)(regmmatch_T *, win_T *, buf_T *, linenr_T, colnr_T, proftime_T *, int *);
+    long	(*regexec_multi)(regmmatch_T *, win_T *, buf_T *, linenr_T, colnr_T, int *);
     //char_u	*expr;
 };