LSB workaround insufficient in qkeymapper_x11.cpp

In qkeymapper_x11.cpp at line 1870, there is the following test:

#ifndef QT_NO_XKB

Within the block that this #ifndef encompasses, there is the following:

#ifdef QT_LINUXBASE
// LSB's IsKeypadKey define is wrong - see
// http://bugs.linuxbase.org/show_bug.cgi?id=2521
#undef IsKeypadKey
#define IsKeypadKey(keysym) \
(((KeySym)(keysym) >= XK_KP_Space) && ((KeySym)(keysym) <= XK_KP_Equal))

#undef IsPrivateKeypadKey
#define IsPrivateKeypadKey(keysym) \
(((KeySym)(keysym) >= 0x11000000) && ((KeySym)(keysym) <= 0x1100FFFF))
#endif

The problem here is that if the XKB module is disabled by the build (as happens in some scenarios when trying to build Qt after configuring with the linux-lsb-g++ mkspec against LSB 4.0 packages), the corrections to IsKeypadKey and IsPrivateKeypadKey do not get picked up, but they are still used in the code further below. The result is a compiler error and thus a broken build.