net: ipv6: Enable IPv6 typeconversion specifier

Add the possibility to recognize IPv6 address in print function.
To output IPv6 address use %pI6 specifier.

Series-changes: 3
- Substituted #if (...) for if (...) to get better readability

Signed-off-by: Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index fe06aa2..530d808 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -450,10 +450,6 @@
  *       decimal for v4 and colon separated network-order 16 bit hex for v6)
  * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
  *       currently the same
- *
- * Note: IPv6 support is currently if(0)'ed out. If you ever need
- * %pI6, please add an IPV6 Kconfig knob, make your code select or
- * depend on that, and change the 0 below to CONFIG_IS_ENABLED(IPV6).
  */
 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 		int field_width, int precision, int flags)
@@ -498,8 +494,7 @@
 		flags |= SPECIAL;
 		/* Fallthrough */
 	case 'I':
-		/* %pI6 currently unused */
-		if (0 && fmt[1] == '6')
+		if (IS_ENABLED(CONFIG_IPV6) && fmt[1] == '6')
 			return ip6_addr_string(buf, end, ptr, field_width,
 					       precision, flags);
 		if (fmt[1] == '4')