intel_ips: fix sparse non-ANSI function warning

Fix sparse warning for non-ANSI function declaration:

drivers/platform/x86/intel_ips.c:1477:25: warning: non-ANSI function declaration of function 'ips_link_to_i915_driver'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/intel_ips.c

@@ -1474,7 +1474,7 @@ ips_gpu_turbo_enabled(struct ips_driver *ips)
 }
 
 void
-ips_link_to_i915_driver()
+ips_link_to_i915_driver(void)
 {
 	/* We can't cleanly get at the various ips_driver structs from
 	 * this caller (the i915 driver), so just set a flag saying