drm/xe/pf: Fix CFI failure in debugfs access

drm/xe/pf: Fix CFI failure in debugfs access

Reading debugfs file (/sys/kernel/debug/dri/0/gt*/pf/adverse_events)
with CFI (Control Flow Integrity) enabled, the kernel panics at
xe_gt_debugfs_simple_show+0x82/0xc0.

xe_gt_debugfs_simple_show() declare a function pointer expecting int
return type, but xe_gt_sriov_pf_monitor_print_events() is void return
type, leading to CFI failure and kernel panic.

[507620.973657] CFI failure at xe_gt_debugfs_simple_show+0x82/0xc0 [xe]
(target: xe_gt_sriov_pf_monitor_print_events+0x0/0x130 [xe]; expected
type: 0xd72c7139)

Fix xe_gt_sriov_pf_monitor_print_events() function by updating to return
an int type.

Fixes: 1c99d3d3edab ("drm/xe/pf: Expose PF monitor details via debugfs")
Signed-off-by: Mohanram Meenakshisundaram <mohanram.meenakshisundaram@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20260514174918.1556357-2-mohanram.meenakshisundaram@intel.com
(cherry picked from commit ff1d386a8359746d9699ac30336e3b0684c68958)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>