Fix compilation with uClibc

Ported from
https://github.com/stschake/buildroot-grasshopper/blob/master/package/torsmo/torsmo-0.18-uclibc-getloadavg.patch

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>

diff -uwNr vdr-2.3.1.org/skinlcars.c vdr-2.3.1/skinlcars.c
--- vdr-2.3.1.org/skinlcars.c	2015-09-01 12:07:07.000000000 +0200
+++ vdr-2.3.1/skinlcars.c	2016-07-31 21:00:11.000000000 +0200
@@ -1100,6 +1100,44 @@
      }
 }
 
+/* uclibc and dietlibc do not have this junk -ReneR */
+#if defined (__UCLIBC__) || defined (__dietlibc__)
+int getloadavg (double loadavg[], int nelem)
+{
+  int fd;
+
+  fd = open ("/proc/loadavg", O_RDONLY);
+  if (fd < 0)
+    return -1;
+  else
+    {
+      char buf[65], *p;
+      ssize_t nread;
+      int i;
+
+      nread = read (fd, buf, sizeof buf - 1);
+      close (fd);
+      if (nread <= 0)
+	return -1;
+      buf[nread - 1] = '\0';
+
+      if (nelem > 3)
+	nelem = 3;
+      p = buf;
+      for (i = 0; i < nelem; ++i)
+	{
+	  char *endp;
+	  loadavg[i] = strtod (p, &endp);
+	  if (endp == p)
+	    return -1;
+	  p = endp;
+	}
+
+      return i;
+    }
+}
+#endif
+
 void cSkinLCARSDisplayMenu::DrawLoad(void)
 {
   if (yb04) {