[newlib-cygwin] Implement SIOCGIFALIAS.

[newlib-cygwin] Implement SIOCGIFALIAS.

[Sebastian Huber]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=b8e36b9251f938a32958cdfb7adac59c04a4a5ee

commit b8e36b9251f938a32958cdfb7adac59c04a4a5ee
Author: Andrey V. Elsukov <ae@FreeBSD.org>
Date:   Wed Oct 14 09:22:54 2020 +0000

    Implement SIOCGIFALIAS.
    
    It is lightweight way to check if an IPv4 address exists.
    
    Submitted by:   Roy Marples
    Reviewed by:    gnn, melifaro
    MFC after:      2 weeks
    Differential Revision:  https://reviews.freebsd.org/D26636

Diff:
---
 newlib/libc/sys/rtems/include/sys/sockio.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/newlib/libc/sys/rtems/include/sys/sockio.h b/newlib/libc/sys/rtems/include/sys/sockio.h
index 03502d770..93b8af28e 100644
--- a/newlib/libc/sys/rtems/include/sys/sockio.h
+++ b/newlib/libc/sys/rtems/include/sys/sockio.h
@@ -84,6 +84,7 @@
 #define	SIOCGIFDESCR	_IOWR('i', 42, struct ifreq)	/* get ifnet descr */ 
 #define	SIOCAIFADDR	 _IOW('i', 43, struct ifaliasreq)/* add/chg IF alias */
 #define	SIOCGIFDATA	 _IOW('i', 44, struct ifreq)	/* get if_data */
+#define	SIOCGIFALIAS	_IOWR('i', 45, struct ifaliasreq)/* get IF alias */
 
 #define	SIOCADDMULTI	 _IOW('i', 49, struct ifreq)	/* add m'cast addr */
 #define	SIOCDELMULTI	 _IOW('i', 50, struct ifreq)	/* del m'cast addr */