ACPI: inline trivial acpi_os_get_thread_id()

acpi_os_get_thread_id() is used only for debugging
code that is not enabled on Linux, so stub it out.

Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 13b5fd5..56d97f1 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -896,14 +896,6 @@
 }
 #endif
 
-u32 acpi_os_get_thread_id(void)
-{
-	if (!in_atomic())
-		return current->pid;
-
-	return 0;
-}
-
 acpi_status acpi_os_signal(u32 function, void *info)
 {
 	switch (function) {
diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h
index 2f5bb5b..b5655a6 100644
--- a/include/acpi/platform/aclinux.h
+++ b/include/acpi/platform/aclinux.h
@@ -99,4 +99,8 @@
 
 #define acpi_cpu_flags unsigned long
 
+#define acpi_thread_id u32
+
+static inline acpi_thread_id acpi_os_get_thread_id(void) { return 0; }
+
 #endif				/* __ACLINUX_H__ */