net/mlx5: Fix build -Wframe-larger-than warnings

net/mlx5: Fix build -Wframe-larger-than warnings

When building, the following warnings will appear.
"
pci_irq.c: In function ‘mlx5_ctrl_irq_request’:
pci_irq.c:494:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=]

pci_irq.c: In function ‘mlx5_irq_request_vector’:
pci_irq.c:561:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=]

eq.c: In function ‘comp_irq_request_sf’:
eq.c:897:1: warning: the frame size of 1080 bytes is larger than 1024 bytes [-Wframe-larger-than=]

irq_affinity.c: In function ‘irq_pool_request_irq’:
irq_affinity.c:74:1: warning: the frame size of 1048 bytes is larger than 1024 bytes [-Wframe-larger-than=]
"

These warnings indicate that the stack frame size exceeds 1024 bytes in
these functions.

To resolve this, instead of allocating large memory buffers on the stack,
it is better to use kvzalloc to allocate memory dynamically on the heap.
This approach reduces stack usage and eliminates these frame size warnings.

Acked-by: Junxian Huang <huangjunxian6@hisilicon.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250722212023.244296-1-yanjun.zhu@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>