cxl/cper: Fix non-ACPI-APEI-GHES build

If ACPI_APEI_GHES is not configured the [un]register work functions are
not properly declared.

0day notices that the cxl_cper_register_work() declaration in the
CONFIG_ACPI_APEI_GHES=n is broken, fix it to be typical nop stub.

Reported-by: kernel test robot <[email protected]>
Closes: http://lore.kernel.org/r/[email protected]
Reviewed-by: Dan Williams <[email protected]>
Signed-off-by: Ira Weiny <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Dave Jiang <[email protected]>

Author: weiny2

include/linux/cxl-event.h

@@ -164,12 +164,12 @@ int cxl_cper_register_work(struct work_struct *work);
 int cxl_cper_unregister_work(struct work_struct *work);
 int cxl_cper_kfifo_get(struct cxl_cper_work_data *wd);
 #else
-static inline int cxl_cper_register_work(struct work_struct *work);
+static inline int cxl_cper_register_work(struct work_struct *work)
 {
 	return 0;
 }
 
-static inline int cxl_cper_unregister_work(struct work_struct *work);
+static inline int cxl_cper_unregister_work(struct work_struct *work)
 {
 	return 0;
 }