xcb: don't allow isAtLeastXI2{1,2} in builds without Xinput2

.. thus making it purely into a _runtime_ check of XInput 2 version.

If Qt was build with -no-xinput2, it does not make sense to compile
in code that always returns "false". Simply exclude code that is not
relevant for -no-xinput2 builds with XCB_USE_XINPUT2 ifdefs. In
addition, this improves readability of the code.

Now, trying to use ::isAtLeastXI21() in a -no-xinput2 build will
result in the following build error:

error: ‘class QXcbConnection’ has no member named ‘isAtLeastXI21’

Change-Id: If242510d43d71829b327edc1f76322f3a0db0e08
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

0 files changed, 0 insertions, 0 deletions