patch 8.2.2171: valgrind warning for using uninitialized value

Problem:    Valgrind warning for using uninitialized value.
Solution:   Do not use "startp" or "endp" unless there is a match.
diff --git a/src/regexp_nfa.c b/src/regexp_nfa.c
index da80ee9..cbfed49 100644
--- a/src/regexp_nfa.c
+++ b/src/regexp_nfa.c
@@ -7236,7 +7236,7 @@
 			|| (end->lnum == start->lnum && end->col < start->col))
 	    rex.reg_mmatch->endpos[0] = rex.reg_mmatch->startpos[0];
     }
-    else
+    else if (retval > 0)
     {
 	if (rex.reg_match->endp[0] < rex.reg_match->startp[0])
 	    rex.reg_match->endp[0] = rex.reg_match->startp[0];
diff --git a/src/version.c b/src/version.c
index 6e2e6ab..d149c9b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2171,
+/**/
     2170,
 /**/
     2169,