net: hibmcge: fix rx buf avl irq is not re-enabled in irq_handle issue

irq initialized with the macro HBG_ERR_IRQ_I will automatically
be re-enabled, whereas those initialized with the macro HBG_IRQ_I
will not be re-enabled.

Since the rx buf avl irq is initialized using the macro HBG_IRQ_I,
it needs to be actively re-enabled;
otherwise priv->stats.rx_fifo_less_empty_thrsld_cnt cannot be
correctly incremented.

Fixes: fd394a33 ("net: hibmcge: Add support for abnormal irq handling feature")
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20251025014642.265259-2-shaojijie@huawei.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>