ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled

Though CONFIG_ACPI_PPTT is selected by platforms and nor user visible,
it may be useful to support the build with CONFIG_ACPI_PPTT disabled.

This patch adds the missing dummy/boiler plate implementation to fix
the build.

Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 032e12a..d2639cd2 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1297,8 +1297,23 @@ static inline int lpit_read_residency_count_address(u64 *address)
 }
 #endif
 
+#ifdef CONFIG_ACPI_PPTT
 int find_acpi_cpu_topology(unsigned int cpu, int level);
 int find_acpi_cpu_topology_package(unsigned int cpu);
 int find_acpi_cpu_cache_topology(unsigned int cpu, int level);
+#else
+static inline int find_acpi_cpu_topology(unsigned int cpu, int level)
+{
+	return -EINVAL;
+}
+static inline int find_acpi_cpu_topology_package(unsigned int cpu)
+{
+	return -EINVAL;
+}
+static inline int find_acpi_cpu_cache_topology(unsigned int cpu, int level)
+{
+	return -EINVAL;
+}
+#endif
 
 #endif	/*_LINUX_ACPI_H*/