drm/radeon: use NULL instead of zero in clearstate headers

Signed-off-by: Michele Curti <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/radeon/clearstate_cayman.h

···
     {SECT_CONTEXT_def_5, 0x0000a29e, 5 },
     {SECT_CONTEXT_def_6, 0x0000a2a5, 56 },
     {SECT_CONTEXT_def_7, 0x0000a2de, 290 },
-    { 0, 0, 0 }
+    { NULL, 0, 0 }
 };
 static const u32 SECT_CLEAR_def_1[] =
 {
···
 static const struct cs_extent_def SECT_CLEAR_defs[] =
 {
     {SECT_CLEAR_def_1, 0x0000ffc0, 3 },
-    { 0, 0, 0 }
+    { NULL, 0, 0 }
 };
 static const u32 SECT_CTRLCONST_def_1[] =
 {
···
 static const struct cs_extent_def SECT_CTRLCONST_defs[] =
 {
     {SECT_CTRLCONST_def_1, 0x0000f3fc, 2 },
-    { 0, 0, 0 }
+    { NULL, 0, 0 }
 };
 static const struct cs_section_def cayman_cs_data[] = {
     { SECT_CONTEXT_defs, SECT_CONTEXT },
     { SECT_CLEAR_defs, SECT_CLEAR },
     { SECT_CTRLCONST_defs, SECT_CTRLCONST },
-    { 0, SECT_NONE }
+    { NULL, SECT_NONE }
 };

drivers/gpu/drm/radeon/clearstate_ci.h

···
     {ci_SECT_CONTEXT_def_5, 0x0000a2a0, 2 },
     {ci_SECT_CONTEXT_def_6, 0x0000a2a3, 1 },
     {ci_SECT_CONTEXT_def_7, 0x0000a2a5, 233 },
-    { 0, 0, 0 }
+    { NULL, 0, 0 }
 };
 static const struct cs_section_def ci_cs_data[] = {
     { ci_SECT_CONTEXT_defs, SECT_CONTEXT },
-    { 0, SECT_NONE }
+    { NULL, SECT_NONE }
 };

drivers/gpu/drm/radeon/clearstate_si.h

···
     {si_SECT_CONTEXT_def_5, 0x0000a2a1, 1 },
     {si_SECT_CONTEXT_def_6, 0x0000a2a3, 1 },
     {si_SECT_CONTEXT_def_7, 0x0000a2a5, 233 },
-    { 0, 0, 0 }
+    { NULL, 0, 0 }
 };
 static const struct cs_section_def si_cs_data[] = {
     { si_SECT_CONTEXT_defs, SECT_CONTEXT },
-    { 0, SECT_NONE }
+    { NULL, SECT_NONE }
 };