Cycles: Add CPU compat headers to some of the OSL implementation files

This header was already included into some of the implementation files already,
and this change is needed for some upcoming changes in the way how kernel_types.h
works.

intern/cycles/kernel/osl/bsdf_diffuse_ramp.cpp

@@ -34,6 +34,7 @@
 
 #include <OSL/genclosure.h>
 
+#include "kernel_compat_cpu.h"
 #include "osl_closures.h"
 
 #include "kernel_types.h"

intern/cycles/kernel/osl/bsdf_phong_ramp.cpp

@@ -34,6 +34,7 @@
 
 #include <OSL/genclosure.h>
 
+#include "kernel_compat_cpu.h"
 #include "osl_closures.h"
 
 #include "kernel_types.h"

intern/cycles/kernel/osl/osl_bssrdf.cpp

@@ -34,6 +34,7 @@
 
 #include <OSL/genclosure.h>
 
+#include "kernel_compat_cpu.h"
 #include "osl_bssrdf.h"
 #include "osl_closures.h"