Avoid double definition of struct ifmap, struct ifconf,
etc. with musl libc.

--- media/mtransport/third_party/nICEr/src/stun/addrs.c	2015-07-14 00:06:51.000000000 +0200
+++ media/mtransport/third_party/nICEr/src/stun/addrs.c	2015-08-21 13:08:44.161155194 +0200
@@ -44,7 +44,7 @@
 #else   /* UNIX */
 #include <sys/param.h>
 #include <sys/socket.h>
-#ifndef ANDROID
+#if !defined(ANDROID) && defined(__GLIBC__)
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
 #else
@@ -62,11 +62,13 @@
 #include <net/if_types.h>
 #include <sys/sockio.h>
 #else
+#if defined(__GLIBC__)
 #include <linux/sockios.h>
 #include <linux/if.h>
+#endif
 #include <linux/kernel.h>
+#if !defined(ANDROID) && defined(__GLIBC__)
 #include <linux/wireless.h>
-#ifndef ANDROID
 #include <linux/ethtool.h>
 #endif
 #endif
@@ -616,7 +618,7 @@
 
 #ifdef LINUX
       int si = sizeof(struct ifreq);
-#ifndef ANDROID
+#if !defined(ANDROID) && defined(__GLIBC__)
       struct ethtool_cmd ecmd;
       struct iwreq wrq;
 #endif
@@ -642,7 +644,7 @@
       else {
           addrs[n].interface.type = NR_INTERFACE_TYPE_UNKNOWN;
           addrs[n].interface.estimated_speed = 0;
-#if defined(LINUX) && !defined(ANDROID)
+#if defined(LINUX) && defined(__GLIBC__) && !defined(ANDROID)
           /* TODO (Bug 896851): interface property for Android */
           /* Getting ethtool for ethernet information. */
           ecmd.cmd = ETHTOOL_GSET;