fix abs family for -0 value

srcs/ft_abs.c

@@ -6,9 +6,7 @@
 
 int ft_abs(int n)
 {
-	if (n < 0)
-		n *= -1;
-	else if (n == 0)
-		n = 0; // for -0
+	if (n <= 0)
+		n *= -1; // also works for -0
 	return (n);
 }

srcs/ft_fabs.c

@@ -6,9 +6,7 @@
 
 double ft_fabs(double n)
 {
-	if (n < 0)
-		n *= -1;
-	else if (n == 0)
-		n = 0; // for -0
+	if (n <= 0)
+		n *= -1; // also works for -0
 	return (n);
 }

srcs/ft_labs.c

@@ -7,8 +7,6 @@
 long int ft_labs(long int n)
 {
 	if (n <= 0)
-		n *= -1;
-	else if (n == 0)
-		n = 0; // for -0
+		n *= -1; // also works for -0
 	return (n);
 }