write HOST_QT_TOOLS to qmodule.pri instead of qhost.pri

its only consumer is qt_tool.prf, which is an internal api.

Change-Id: Iae90b079c5af60efad2ded70d6ea481212e5353a
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

configure

@@ -667,7 +667,6 @@ while [ "$#" -gt 0 ]; do
         ;;
     external-hostbindir)
         CFG_HOST_QT_TOOLS_PATH="$VAL"
-        HostVar set HOST_QT_TOOLS "$VAL"
         ;;
     bindir)
         QT_INSTALL_BINS="$VAL"

configure.pri

@@ -648,6 +648,15 @@ defineReplace(qtConfOutputPostProcess_publicPro) {
     return($$output)
 }
 
+defineReplace(qtConfOutputPostProcess_privatePro) {
+    output = $$1
+
+    !isEmpty(config.input.external-hostbindir): \
+        output += "HOST_QT_TOOLS = $$val_escape(config.input.external-hostbindir)"
+
+    return($$output)
+}
+
 defineReplace(qtConfOutputPostProcess_publicHeader) {
     qt_version = $$[QT_VERSION]
     output = \

mkspecs/features/qt_tool.prf

@@ -27,7 +27,7 @@ DEFINES *= QT_USE_QSTRINGBUILDER
 
     vars = binary depends
 
-    isEmpty(HOST_QT_TOOLS) {
+    !host_build|isEmpty(HOST_QT_TOOLS) {
         load(resolve_target)
 
         !host_build|!force_bootstrap: MODULE_DEPENDS = $$replace(QT, -private$, _private)