net: xilinx: axienet: Fix IRQ error handling

irq_of_parse_and_map() returns 0 when parsing or mapping an IRQ fails,
while platform_get_irq() returns a negative error code on failure.

Handle both failure cases appropriately: return -EINVAL when
irq_of_parse_and_map() fails, and propagate the original error code
returned by platform_get_irq() instead of returning -ENOMEM.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Suraj Gupta <suraj.gupta2@amd.com>
Link: https://patch.msgid.link/20260909045450.16176-4-phucduc.bui@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>