Patch from fcolista

diff --git a/core/cmake/distname.sh b/core/cmake/distname.sh
index d52308c..603d249 100755
--- a/core/cmake/distname.sh
+++ b/core/cmake/distname.sh
@@ -45,7 +45,7 @@ else
             DISTNAME=univention
             ;;
          *)
-            DISTNAME=""
+            DISTNAME="alpine"
             ;;
       esac
 
@@ -165,6 +165,10 @@ else
       elif test "$CYGWIN" = yes
       then
          DISTNAME=cygwin
+      elif test -f /etc/alpine-release
+      then
+         DISTNAME=alpine
+         DISTVER=`cat /etc/alpine-release`
       else
          DISTNAME=unknown
          DISTVER=unknown