RDMA/ionic: Fix build failure on SPARC due to xchg() operand size

RDMA/ionic: Fix build failure on SPARC due to xchg() operand size

xchg() is used to safely handle the event queue arming.
However SPARC xchg operates only 4B of variable.
Change variable type from bool to int.

Unverified Error/Warning (likely false positive, kindly check if interested):

    ERROR: modpost: "__xchg_called_with_bad_pointer" [drivers/infiniband/hw/ionic/ionic_rdma.ko] undefined!

Error/Warning ids grouped by kconfigs:

recent_errors
`-- sparc-allmodconfig
    `-- ERROR:__xchg_called_with_bad_pointer-drivers-infiniband-hw-ionic-ionic_rdma.ko-undefined

Fixes: f3bdbd42702c ("RDMA/ionic: Create device queues to support admin operations")
Reported-by: Leon Romanovsky <leon@kernel.org>
Closes: https://lore.kernel.org/lkml/20250918180750.GA135135@unreal/
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Link: https://patch.msgid.link/20250919121301.1113759-1-abhijit.gangurde@amd.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>