bm60rgb_iso: add underglow support (#10307)

* add underglow definition

keyboards/bm60rgb_iso/bm60rgb_iso.c

@@ -32,7 +32,9 @@ led_config_t g_led_config = { {
     // LShift, <, Z, X, C, V, B, N, M, ,, ., /, Shift, Up,
     {   3,  48 }, {  22,  48 }, {  33,  48 }, {  48,  48 }, {  63,  48 }, {  78,  48 }, {  93,  48 }, { 108,  48 }, { 123,  48 }, { 138,  48 }, { 153,  48 }, { 168,  48 }, { 194,  48 }, { 213,  48 }, 
     // Ctrl, GUI, Alt, Space, RAlt, FN, Left, Down, Right
-    {   3,  64 }, {  22,  64 }, {  33,  64 }, { 101,  64 }, { 135,  64 }, { 153,  64 }, { 195,  64 }, { 210,  64 }, { 225,  64 }
+    {   3,  64 }, {  22,  64 }, {  33,  64 }, { 101,  64 }, { 135,  64 }, { 153,  64 }, { 195,  64 }, { 210,  64 }, { 225,  64 },
+    // UNDERGLOW
+    {   216, 32 }, {  180,  32 }, {  144, 32 }, { 108,  32 }, { 72,  32 }, { 36,  32 }
 }, {
     // Esc, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, -, =, Backspace
     4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 1, 
@@ -43,6 +45,8 @@ led_config_t g_led_config = { {
     // LShift,<, Z, X, C, V, B, N, M, ,, ., Shift, Up, / 
     1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 1, 4, 
     // Ctrl, GUI, Alt, Space, RAlt, FN, Left, Down, Right
-    1, 1, 1, 4, 1, 1, 1, 1, 1
+    1, 1, 1, 4, 1, 1, 1, 1, 1,
+    // UNDERGLOW
+    2, 2, 2, 2, 2, 2
 } };
 #endif