Fix zeroconf support on Alpine Linux (#1155)

NEWS

@@ -6,6 +6,7 @@ Changes in 2.4.2
 * UPD: meson: Add option to override system WolfSSL
        with embedded WolfSSL: `with-ssl-override', GitHub #1175
 * UPD: Remove obsolete Red Hat Upstart and SuSE SysV init scripts, GitHub #1162
+* FIX: Restore Zeroconf functionality for Alpine Linux, GitHub #1198
 * FIX: meson: Fix errors in PAM support macro, GitHub #1179
 * FIX: meson: Fix perl shebang substitution in cnid2_create script, GitHub #1184
 * FIX: meson: Fix errors in shadow password macro, GitHub #1191

meson.build

@@ -721,7 +721,7 @@ avahi = dependency('avahi-client', required: false)
 
 dns_sd_libs = []
 
-dns_sd = cc.find_library('dns_sd', has_headers: 'dns_sd.h', required: false)
+dns_sd = cc.find_library('dns_sd', required: false)
 if dns_sd.found()
     dns_sd_libs += dns_sd
 endif
@@ -735,7 +735,7 @@ zeroconf_provider = ''
 freebsd_zeroconf_daemon = ''
 
 have_dns = (
-    (dns_sd.found() or system.found())
+    (dns_sd.found() or system.found()) and cc.has_header('dns_sd.h')
     and cc.has_function(
         'DNSServiceRegister',
         dependencies: dns_sd_libs,