console: Print out complete stdio device list

At present if both CONSOLE_MUX and SYS_CONSOLE_IS_IN_ENV are on,
during boot, the printed out stdio devices are incomplete, e.g.:
with "stdout=serial,vidconsole", only "vidconsole" is printed.

For such case, we can print out the stdio device name from the
environment variables.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

common/console.c

@@ -1014,6 +1014,17 @@ static void stdio_print_current_devices(void)
 {
 	char *stdinname, *stdoutname, *stderrname;
 
+	if (CONFIG_IS_ENABLED(CONSOLE_MUX) &&
+	    CONFIG_IS_ENABLED(SYS_CONSOLE_IS_IN_ENV)) {
+		/* stdin stdout and stderr are in environment */
+		stdinname  = env_get("stdin");
+		stdoutname = env_get("stdout");
+		stderrname = env_get("stderr");
+
+		stdinname = stdinname ? : "No input devices available!";
+		stdoutname = stdoutname ? : "No output devices available!";
+		stderrname = stderrname ? : "No error devices available!";
+	} else {
 		stdinname = stdio_devices[stdin] ?
 			stdio_devices[stdin]->name :
 			"No input devices available!";
@@ -1023,6 +1034,7 @@ static void stdio_print_current_devices(void)
 		stderrname = stdio_devices[stderr] ?
 			stdio_devices[stderr]->name :
 			"No error devices available!";
+	}
 
 	/* Print information */
 	puts("In:    ");