staging: r8188eu: change all num...Q variables to u8

All of numPubQ, numHQ and numLQ variables store only u8 values. Change
their types to u8. We can then simplify the REG_RQPN expression. The
macros and the temporary variable are not needed any more.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220808201405.68966-4-martin@kaiser.cx


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>