RDMA/efa: Fix use of completion ctx after free

RDMA/efa: Fix use of completion ctx after free

On admin queue completion handling, if the admin command completed with
error we print data from the completion context. The issue is that we
already freed the completion context in polling/interrupts handler which
means we print data from context in an unknown state (it might be
already used again).
Change the admin submission flow so alloc/dealloc of the context will be
symmetric and dealloc will be called after any potential use of the
context.

Fixes: 68fb9f3e312a ("RDMA/efa: Remove redundant NULL pointer check of CQE")
Reviewed-by: Daniel Kranzdorf <dkkranzd@amazon.com>
Reviewed-by: Michael Margolin <mrgolin@amazon.com>
Signed-off-by: Yonatan Nachum <ynachum@amazon.com>
Link: https://patch.msgid.link/20260308165350.18219-1-ynachum@amazon.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>