cmake: Match tense of other log output

Change-Id: Ied164c97bd54f6b37450d7a2cf8225ee5190ce17
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

cmake/QtPostProcess.cmake

@@ -1,6 +1,6 @@
 function(qt_internal_write_depends_file module)
     set(outfile "${QT_BUILD_DIR}/${INSTALL_INCLUDEDIR}/${module}/${module}Depends")
-    message("Generate ${outfile}...")
+    message("Generating ${outfile}...")
     set(contents "/* This file was generated by cmake with the info from ${module} target. */\n")
     string(APPEND contents "#ifdef __cplusplus /* create empty PCH in C mode */\n")
     foreach (m ${ARGN})