term, term.ui: fix a panic on !=linux unixes when running examples/term.ui/

vlib/term/declarations_default.c.v

@@ -6,5 +6,5 @@ mut:
 	c_oflag int
 	c_cflag int
 	c_lflag int
-	c_cc    [10]int
+	c_cc    [20]byte
 }

vlib/term/ui/declarations_default.c.v

@@ -1,10 +1,10 @@
 module ui
 
-struct C.termios {
+pub struct C.termios {
 mut:
 	c_iflag int
 	c_oflag int
 	c_cflag int
 	c_lflag int
-	c_cc    [10]int
+	c_cc    [20]byte
 }