Manually editing mkspec or sysroot for kits works strange

Editing the mkspec or the sysroot moves the cursor to the end of the current text inside the QLineEdit after each typed character.

Steps to reproduce:

• open Creator's Settings dialog
• edit the mkspec or sysroot of an existing kit - do this by editing something in front or in the middle of the already existing text

Expected behaviour:

• no automatical movement of the cursor after each typed key