Define a value for SYS_F_FCNTL

This symbol was added in commit d33b215b33
but was only used in certain (presumed uncommon) preprocessor conditionals,
as no build failures have been reported yet.

Reported by Balaji Marisetti.

Closes: #4029

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4030)

crypto/err/err.c

@@ -89,6 +89,7 @@ static ERR_STRING_DATA ERR_str_functs[] = {
     {ERR_PACK(0, SYS_F_CLOSE, 0), "close"},
     {ERR_PACK(0, SYS_F_IOCTL, 0), "ioctl"},
     {ERR_PACK(0, SYS_F_STAT, 0), "stat"},
+    {ERR_PACK(0, SYS_F_FCNTL, 0), "fcntl"},
     {0, NULL},
 };
 

include/openssl/err.h

@@ -165,6 +165,7 @@ typedef struct err_state_st {
 # define SYS_F_CLOSE             20
 # define SYS_F_IOCTL             21
 # define SYS_F_STAT              22
+# define SYS_F_FCNTL             23
 
 /* reasons */
 # define ERR_R_SYS_LIB   ERR_LIB_SYS/* 2 */