re PR bootstrap/51201 (build error without Ada compiler installed)

	PR bootstrap/51201
	* gcc-interface/Make-lang.in: Initialize RTS_DIR with = instead of :=.

From-SVN: r181877

gcc/ada/ChangeLog

+2011-12-01  Jakub Jelinek  <jakub@redhat.com>
+
+	PR bootstrap/51201
+	* gcc-interface/Make-lang.in: Initialize RTS_DIR with = instead of :=.
+
 2011-11-24  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* s-taprop-tru64.adb (Create_Task): Use Unrestricted_Access.

gcc/ada/gcc-interface/Make-lang.in

@@ -118,7 +118,7 @@ ifeq ($(build), $(host))
 
     # put the host RTS dir first in the PATH to hide the default runtime
     # files that are among the sources
-    RTS_DIR:=$(strip $(subst \,/,$(shell gnatls -v | grep adalib )))
+    RTS_DIR=$(strip $(subst \,/,$(shell gnatls -v | grep adalib )))
 
     ADA_TOOLS_FLAGS_TO_PASS=\
         CC="$(CC)" \
@@ -153,7 +153,7 @@ else
   else
     # This is a canadian cross. We should use a toolchain running on the
     # build platform and targeting the host platform.
-    RTS_DIR:=$(strip $(subst \,/,$(shell $(GNATLS_FOR_HOST) -v | grep adalib )))
+    RTS_DIR=$(strip $(subst \,/,$(shell $(GNATLS_FOR_HOST) -v | grep adalib )))
     ADA_TOOLS_FLAGS_TO_PASS=\
         CC="$(CC)" \
         $(COMMON_FLAGS_TO_PASS) $(ADA_FLAGS_TO_PASS)  \