ACPI: Handle CONFIG_ACPI=n better from linux/acpi.h

linux/acpi.h is the top level header for interfacing
with the ACPI sub-system, so acpi_disabled should be
up there instead of down in asm/acpi.h -- particularly
since asm/acpi.h doesn't exist for all architectures.

Same story for acpi_table_parse(), which is a top-level
API to Linux/ACPI.

This is necessary for building some code that
used to always depend on CONFIG_ACPI=y, but will soon
also need to build with CONFIG_ACPI=n.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 34321cf..3fce811 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -292,7 +292,10 @@
 extern acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags);
 extern void acpi_early_init(void);
 
-#else	/* CONFIG_ACPI */
+#else	/* !CONFIG_ACPI */
+
+#define acpi_disabled 1
+
 static inline void acpi_early_init(void) { }
 
 static inline int early_acpi_boot_init(void)
@@ -331,5 +334,11 @@
 	return 0;
 }
 
+struct acpi_table_header;
+static inline int acpi_table_parse(char *id,
+				int (*handler)(struct acpi_table_header *))
+{
+	return -1;
+}
 #endif	/* !CONFIG_ACPI */
 #endif	/*_LINUX_ACPI_H*/