Throughout, change USE_CYGSERVER to USE_SERVER.

* Makefile.in (LIBSERVER): Define and use.
* configure.in: Set LIBSERVER as appropriate.
* environ.cc: Rename allow_daemon to allow_server.  Only recognize when
USE_SERVER is defined.

winsup/cygwin/configure

@@ -1904,11 +1904,13 @@ fi
 if test "${enable_server+set}" = set; then
   enableval="$enable_server"
   case "${enableval}" in
-yes)	 cat >> confdefs.h <<\EOF
-#define USE_CYGSERVER 1
+yes)
+	 cat >> confdefs.h <<\EOF
+#define USE_SERVER 1
 EOF
- ;;
-no)	 ;;
+
+	 LIBSERVER='$(bupdir)/cygserver/libcygserver.a' ;;
+no)	 LIBSERVER=;;
 esac
 
 fi
@@ -1966,6 +1968,7 @@ esac
 
 
 
+
 trap '' 1 2 15
 cat > confcache <<\EOF
 # This file is a shell script that caches the results of configure
@@ -2132,6 +2135,7 @@ s%@CPP@%$CPP%g
 s%@ALLOCA@%$ALLOCA%g
 s%@SET_MAKE@%$SET_MAKE%g
 s%@MALLOC_OFILES@%$MALLOC_OFILES%g
+s%@LIBSERVER@%$LIBSERVER%g
 s%@DLL_ENTRY@%$DLL_ENTRY%g
 s%@DEF_DLL_ENTRY@%$DEF_DLL_ENTRY%g
 s%@CONFIG_DIR@%$CONFIG_DIR%g