File flush-intrins.patch of Package ftnchek

--- ftnchek/intrins.c.orig	2020-09-10 10:42:04.946051194 +0200
+++ ftnchek/intrins.c	2020-09-10 10:42:05.014052840 +0200
@@ -647,6 +647,7 @@ SYSTEM_CLOCK ([COUNT,              Obtai
 #ifdef UNIX_INTRINSICS
 {"ABORT",	1,	STR,	type_SUBROUTINE,I_NONSTD|I_UNIX,NULL},
 {"AND",		2,	I,	type_INTEGER,	I_NONSTD|I_UNIX,NULL},
+{"FLUSH",	I_0or1,	I,	type_SUBROUTINE,I_NONSTD|I_UNIX,NULL},
 		/* I, then STR not enforced in GETARG. */
 {"GETARG",	2,	I|STR,	type_SUBROUTINE,I_MIXED_ARGS|I_NONSTD|I_UNIX,NULL},
 {"GETENV",	2,	STR,	type_SUBROUTINE,I_NONSTD|I_UNIX,NULL},