octeontx2-af: CGX: fix bitmap leaks

octeontx2-af: CGX: fix bitmap leaks

The RX/TX flow-control bitmaps (rx_fc_pfvf_bmap and tx_fc_pfvf_bmap)
are allocated by cgx_lmac_init() but never freed in cgx_lmac_exit().
Unbinding and rebinding the driver therefore triggers kmemleak:

    unreferenced object (size 16):
        backtrace:
          rvu_alloc_bitmap
          cgx_probe

Free both bitmaps during teardown.

Fixes: e740003874ed ("octeontx2-af: Flow control resource management")
Cc: stable@vger.kernel.org
Signed-off-by: Bo Sun <bo@mboxify.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Jijie Shao <shaojijie@huawei.com>
Link: https://patch.msgid.link/20260206130925.1087588-2-bo@mboxify.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>