streamline_config.pl: remove prompt warnings for configs with defaults

Ignore process select warnings for config entries that have a default
option. Some config entries have no prompt, and nothing selects them, but
these config options are okay because they have a default option.

Signed-off-by: David Hunter <[e-mail]>
Signed-off-by: Masahiro Yamada <[e-mail]>

scripts/kconfig/streamline_config.pl

···
 my %prompts;
 my %objects;
 my %config2kfile;
+my %defaults;
 my $var;
 my $iflevel = 0;
 my @ifdeps;
···
 	    $depends{$config} .= " " . $1;
 	} elsif ($state ne "NONE" && /^\s*def(_(bool|tristate)|ault)\s+(\S.*)$/) {
 	    my $dep = $3;
+            $defaults{$config} = 1;
 	    if ($dep !~ /^\s*(y|m|n)\s*$/) {
 		$dep =~ s/.*\sif\s+//;
 		$depends{$config} .= " " . $dep;
···
 
     # If no possible config selected this, then something happened.
     if (!defined($next_config)) {
-	print STDERR "WARNING: $config is required, but nothing in the\n";
-	print STDERR "  current config selects it.\n";
+
+	# Some config options have no prompt, and nothing selects them, but
+	# they stay turned on once the final checks for the configs
+	# are done. These configs have a default option, so turn off the
+	# warnings for configs with default options.
+	if (!defined($defaults{$config})) {
+	    print STDERR "WARNING: $config is required, but nothing in the\n";
+	    print STDERR "  current config selects it.\n";
+	}
+
 	return;
     }