[master] f364fa300 v1l: restore errno on error

[Dridi Boukelmoune]

commit f364fa3008ede474d70c0b35feb2c05b21001388
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Wed Jan 31 17:35:11 2024 +0100

    v1l: restore errno on error
    
    Spotted by Darryl Rodden.

diff --git a/bin/varnishd/http1/cache_http1_line.c b/bin/varnishd/http1/cache_http1_line.c
index 82ae2fe26..b1087d1e6 100644
--- a/bin/varnishd/http1/cache_http1_line.c
+++ b/bin/varnishd/http1/cache_http1_line.c
@@ -253,6 +253,7 @@ V1L_Flush(const struct worker *wrk)
 				v1l->werr = SC_REM_CLOSE;
 			else
 				v1l->werr = SC_TX_ERROR;
+			errno = err;
 		}
 	}
 	v1l->liov = 0;