feature (kernel): implemented function to get absolute number

kernel/inc/utils/math.h

@@ -24,5 +24,6 @@
 #define FLOOR_TO(a, b)  (a     - (a % b))
 
 uint64_t pow(uint64_t base, uint64_t exp);
+uint64_t abs(int64_t n);
 
 #endif //NOX_MATH_H

kernel/src/utils/math.c

@@ -22,3 +22,10 @@ uint64_t pow(uint64_t base, uint64_t exp) {
     }
     return n;
 }
+
+uint64_t abs(int64_t n) {
+    if (n < 0) {
+        return n * -1;
+    }
+    return n;
+}