octeontx2-pf: Avoid use of GFP_KERNEL in atomic context

In the Linux kernel, the following vulnerability has been resolved:

octeontx2-pf: Avoid use of GFP_KERNEL in atomic context

Using GFP_KERNEL in preemption disable context, causing below warning
when CONFIG_DEBUG_ATOMIC_SLEEP is enabled.

[ 32.542271] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274
[ 32.550883] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
[ 32.558707] preempt_count: 1, expected: 0
[ 32.562710] RCU nest depth: 0, expected: 0
[ 32.566800] CPU: 3 PID: 1 Comm: swapper/0 Tainted: G W 6.2.0-rc2-00269-gae9dcb91c606 #7
[ 32.576188] Hardware name: Marvell CN106XX board (DT)
[ 32.581232] Call trace:
[ 32.583670] dump_backtrace.part.0+0xe0/0xf0
[ 32.587937] show_stack+0x18/0x30
[ 32.591245] dump_stack_lvl+0x68/0x84
[ 32.594900] dump_stack+0x18/0x34
[ 32.598206] __might_resched+0x12c/0x160
[ 32.602122] __might_sleep+0x48/0xa0
[ 32.605689] __kmem_cache_alloc_node+0x2b8/0x2e0
[ 32.610301] __kmalloc+0x58/0x190
[ 32.613610] otx2_sq_aura_pool_init+0x1a8/0x314
[ 32.618134] otx2_open+0x1d4/0x9d0

To avoid use of GFP_ATOMIC for memory allocation, disable preemption
after all memory allocation is done.