Fix name clash with libcap 2.29.

Taken from upstream:
https://github.com/iputils/iputils/commit/18f9a84e0e702841d6cc4d5f593de4fbd1348e83

diff --git a/ninfod/ninfod.c b/ninfod/ninfod.c
--- a/ninfod/ninfod.c
+++ b/ninfod/ninfod.c
@@ -455,7 +455,7 @@ static void do_daemonize(void)
 /* --------- */
 #ifdef HAVE_LIBCAP
 static const cap_value_t cap_net_raw = CAP_NET_RAW;
-static const cap_value_t cap_setuid =  CAP_SETUID; 
+static const cap_value_t cap_setuserid = CAP_SETUID;
 static cap_flag_value_t cap_ok;
 #else
 static uid_t euid;
@@ -487,7 +487,7 @@ static void limit_capabilities(void)
 
 	cap_get_flag(cap_cur_p, CAP_SETUID, CAP_PERMITTED, &cap_ok);
 	if (cap_ok != CAP_CLEAR)
-		cap_set_flag(cap_p, CAP_PERMITTED, 1, &cap_setuid, CAP_SET);
+		cap_set_flag(cap_p, CAP_PERMITTED, 1, &cap_setuserid, CAP_SET);
 
 	if (cap_set_proc(cap_p) < 0) {
 		DEBUG(LOG_ERR, "cap_set_proc: %s\n", strerror(errno));
@@ -520,8 +520,8 @@ static void drop_capabilities(void)
 
 	/* setuid / setuid */
 	if (cap_ok != CAP_CLEAR) {
-		cap_set_flag(cap_p, CAP_PERMITTED, 1, &cap_setuid, CAP_SET);
-		cap_set_flag(cap_p, CAP_EFFECTIVE, 1, &cap_setuid, CAP_SET);
+		cap_set_flag(cap_p, CAP_PERMITTED, 1, &cap_setuserid, CAP_SET);
+		cap_set_flag(cap_p, CAP_EFFECTIVE, 1, &cap_setuserid, CAP_SET);
 
 		if (cap_set_proc(cap_p) < 0) {
 			DEBUG(LOG_ERR, "cap_set_proc: %s\n", strerror(errno));
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<tr><td><span title='2020-10-26 18:04:25 +0100'>2020-10-26</span></td><td><a href='/guix/commit/gnu/packages/patches/python-3-hurd-configure.patch?id=677ce39831c7170e242dca1a874f2420523e2b5e'>gnu: python: Add missing patch.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a follow-up to commit 5319f716cf575321bef4c501d7aebdc7220d69cf.

Reported by efraim via IRC.

* gnu/packages/patches/python-3-hurd-configure.patch: New file.
</span></span></td><td>Jan (janneke) Nieuwenhuizen</td></tr>