acpi: fix section mismatch warning in pnpacpi

Fix following section mismatch warning:
WARNING: vmlinux.o(.text+0x153d69): Section mismatch in reference from the function is_exclusive_device() to the variable .init.data:excluded_id_list

is_exclusive_device is only used from __init context so document
this with the __init annotation and get rid of the warning.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index c283a9a..63e64ef 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -44,7 +44,7 @@
 	{"", 0},
 };
 
-static inline int is_exclusive_device(struct acpi_device *dev)
+static inline int __init is_exclusive_device(struct acpi_device *dev)
 {
 	return (!acpi_match_device_ids(dev, excluded_id_list));
 }