Makefile: add GSOAP_INSTALL_DIR variable

Makefile

@@ -10,7 +10,8 @@ DAEMON_NO_CLOSE_STDIO = 0
 
 
 
-GSOAP_DIR         = ./gsoap-2.8/gsoap
+GSOAP_INSTALL_DIR = ./gsoap-2.8
+GSOAP_DIR         = $(GSOAP_INSTALL_DIR)/gsoap
 GSOAP_PLUGIN_DIR  = $(GSOAP_DIR)/plugin
 GSOAP_IMPORT_DIR  = $(GSOAP_DIR)/import
 
@@ -149,7 +150,7 @@ clean:
 .PHONY: distclean
 distclean: clean
 	-@rm -f -d -R SDK
-	-@rm -f -d -R gsoap-2.8
+	-@rm -f -d -R $(GSOAP_INSTALL_DIR)
 	-@rm -f RECV.log SENT.log TEST.log
 
 
@@ -221,13 +222,13 @@ define build_gsoap
     fi
 
     # unzip
-    if [ ! -f gsoap-2.8/README.txt ]; then \
+    if [ ! -f $(GSOAP_INSTALL_DIR)/README.txt ]; then \
          unzip ./SDK/gsoap.zip; \
     fi
 
     # build
     if [ ! -f $(SOAPCPP2) ] || [ ! -f $(WSDL2H) ]; then \
-         cd gsoap-2.8; \
+         cd $(GSOAP_INSTALL_DIR); \
          ./configure && \
          make -j1; \
          cd ..;\