[Keyboard] Added split plus layout to Cospad (#13938)

keyboards/cospad/cospad.h

@@ -125,6 +125,37 @@
     { k50, ___, k52, ___ } \
 }
 
+/* 6x4 numpad layout with split Plus
+ * ,-------------------.
+ * | 00 | 01 | 02 | 03 |
+ * |----|----|----|----|
+ * | 10 | 11 | 12 | 13 |
+ * |----|----|----|----|
+ * | 20 | 21 | 22 | 23 |
+ * |----|----|----|----|
+ * | 30 | 31 | 32 | 33 |
+ * |----|----|----|----|
+ * | 40 | 41 | 42 |    |
+ * |----|----|----| 43 |
+ * |    50   | 52 |    |
+ * `-------------------'
+ */
+#define LAYOUT_numpad_6x4_split_plus( \
+    k00, k01, k02, k03, \
+    k10, k11, k12, k13, \
+    k20, k21, k22, k23, \
+    k30, k31, k32, k33, \
+    k40, k41, k42, \
+    k50,      k52, k43 \
+) \
+{ \
+    { k00, k01, k02, k03 }, \
+    { k10, k11, k12, k13 }, \
+    { k20, k21, k22, k23 }, \
+    { k30, k31, k32, k33 }, \
+    { k40, k41, k42, k43 }, \
+    { k50, ___, k52, ___ } \
+}
 
 /* 6x4 numpad with split Plus and 0 keys
  * ,-------------------.