staging: rtl8192e: Remove unused variables txbeac.., txman.. and txcmdp..

txbeaconerr, txmanageokint and txcmdpktokint are initialized and increased
but never read. Remove dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/6c922591c48512692f77729ac91849ebb4e61bd1.1674675808.git.philipp.g.hortmann@gmail.com


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