bitmap: fix buffer overrun in bitmap init

bitmap: fix buffer overrun in bitmap init

Bitmap initialization function is allowed to memset()
caller-provided buffer with number of bytes exceeded
this buffer size. This happens due to wrong comparison
sign between buffer size and number of bytes required
to initialize bitmap.

Fixes: 602c9ca33a4 ("sched: bitmap is now dynamically allocated")
Cc: stable@dpdk.org
Reported-by: Andy Moreton <amoreton@xilinx.com>
Signed-off-by: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>