uClibc does not contain gnu/libc-version.h

Patch sent upstream: https://bugs.exim.org/show_bug.cgi?id=2070

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

diff -uNr exim-4.88.org/src/exim.c exim-4.88/src/exim.c
--- exim-4.88.org/src/exim.c	2016-12-18 15:02:28.000000000 +0100
+++ exim-4.88/src/exim.c	2016-12-26 12:12:57.000000000 +0100
@@ -12,7 +12,7 @@
 
 #include "exim.h"
 
-#ifdef __GLIBC__
+#if defined(__GLIBC__) && !defined(__UCLIBC__)
 # include <gnu/libc-version.h>
 #endif
 
@@ -1044,7 +1044,7 @@
   fprintf(f, "Compiler: <unknown>\n");
 #endif
 
-#ifdef __GLIBC__
+#if defined(__GLIBC__) && !defined(__UCLIBC__)
   fprintf(f, "Library version: Glibc: Compile: %d.%d\n",
 	       	__GLIBC__, __GLIBC_MINOR__);
   if (__GLIBC_PREREQ(2, 1))