sdktool: Fix linking on Windows

Amends 959fec76dc.

Change-Id: Ibc51b19b47ec4ba8b408dc2679581b301f1c9667
Reviewed-by: hjk <hjk@qt.io>

src/tools/sdktool/sdktool.pro

@@ -37,6 +37,7 @@ SOURCES += \
     $$UTILS/qtcassert.cpp \
     $$UTILS/qtcprocess.cpp \
     $$UTILS/savefile.cpp \
+    $$UTILS/stringutils.cpp
 
 HEADERS += \
     addabiflavor.h \

src/tools/sdktool/sdktool.qbs

@@ -72,7 +72,8 @@ QtcTool {
             "persistentsettings.cpp", "persistentsettings.h",
             "qtcassert.cpp", "qtcassert.h",
             "qtcprocess.cpp", "qtcprocess.h",
-            "savefile.cpp", "savefile.h"
+            "savefile.cpp", "savefile.h",
+            "stringutils.cpp"
         ]
     }
     Group {