Update the .gitignore file not to have left-over entries

Change-Id: I82005d461818c7c1b637ee6b523a492de6bdb78b
Reviewed-by: Denis Shienkov <denis.shienkov@gmail.com>
Reviewed-by: Sergey Belyashov <Sergey.Belyashov@gmail.com>

.gitignore

@@ -10,12 +10,11 @@ moc_*.cpp
 lib*.so
 lib*.so.*
 .qmake.cache
-include/QtAddOnSerialPort/*
+include/*
 lib/cmake/*
 lib*.la
 lib*.prl
 module-paths/*
-src/qtaddonserialportversion.h
 lib/pkgconfig/*
 Makefile.Debug
 Makefile.Release