mailbox: zynqmp: Remove invalid __percpu annotation in zynqmp_ipi_probe()

struct zynqmp_ipi_pdata __percpu *pdata is not a per-cpu variable,
so it should not be annotated with __percpu annotation.

Remove invalid __percpu annotation to fix several

zynqmp-ipi-mailbox.c:920:15: warning: incorrect type in assignment (different address spaces)
zynqmp-ipi-mailbox.c:920:15:    expected struct zynqmp_ipi_pdata [noderef] __percpu *pdata
zynqmp-ipi-mailbox.c:920:15:    got void *
zynqmp-ipi-mailbox.c:927:56: warning: incorrect type in argument 3 (different address spaces)
zynqmp-ipi-mailbox.c:927:56:    expected unsigned int [usertype] *out_value
zynqmp-ipi-mailbox.c:927:56:    got unsigned int [noderef] __percpu *
...

and several

drivers/mailbox/zynqmp-ipi-mailbox.c:924:9: warning: dereference of noderef expression
...

sparse warnings.

There were no changes in the resulting object file.

Cc: stable@vger.kernel.org
Fixes: 6ffb1635 ("mailbox: zynqmp: handle SGI for shared IPI")
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Tanmay Shah <tanmay.shah@amd.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>