patch 8.2.1936: session sets the local 'scrolloff' value to the global value

Problem:    Session sets the local 'scrolloff' value to the global value.
Solution:   Do not let restoring the global option value change the local
            value.
diff --git a/src/session.c b/src/session.c
index 829cca9..44976e8 100644
--- a/src/session.c
+++ b/src/session.c
@@ -1216,7 +1216,7 @@
 #ifdef FEAT_SESSION
 	if (!failed && view_session)
 	{
-	    if (put_line(fd, "let s:so_save = &so | let s:siso_save = &siso | set so=0 siso=0") == FAIL)
+	    if (put_line(fd, "let s:so_save = &g:so | let s:siso_save = &g:siso | setg so=0 siso=0 | setl so=-1 siso=-1") == FAIL)
 		failed = TRUE;
 	    if (eap->cmdidx == CMD_mksession)
 	    {
@@ -1261,7 +1261,7 @@
 		failed |= (put_view(fd, curwin, !using_vdir, flagp, -1, NULL)
 								      == FAIL);
 	    }
-	    if (put_line(fd, "let &so = s:so_save | let &siso = s:siso_save")
+	    if (put_line(fd, "let &g:so = s:so_save | let &g:siso = s:siso_save")
 								      == FAIL)
 		failed = TRUE;
 #ifdef FEAT_SEARCH_EXTRA