fix code generated to multiple var declaration (#114)

Authored-by: Felipe Pena <felipe.pena@championx.com>

src/c2v.v

@@ -1403,6 +1403,9 @@ fn (mut c C2V) var_decl(mut decl_stmt Node) {
 			}
 			c.gen('${name} := ')
 			c.expr(expr)
+			if decl_stmt.inner.len > 1 {
+				c.gen('\n')
+			}
 		} else {
 			oldtyp := var_decl.ast_type.qualified
 			mut typ := typ_.name

tests/15.multi_var_decl.c

@@ -0,0 +1,3 @@
+int main() {
+int n, r, sum = 0, temp;
+}

tests/15.multi_var_decl.out

@@ -0,0 +1,9 @@
+[translated]
+module main
+
+fn main() {
+	n := 0
+	r := 0
+	sum := 0
+	temp := 0
+}