kconfig: Fix warning: ignoring return value of 'fgets'

This fix facilitates fgets() either it returns on success or on error or
when end of file occurs.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index 010600e..4f0ed5b 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -108,7 +108,7 @@
 		check_stdin();
 	case oldaskconfig:
 		fflush(stdout);
-		fgets(line, 128, stdin);
+		xfgets(line, 128, stdin);
 		return 1;
 	default:
 		break;
@@ -306,7 +306,7 @@
 			check_stdin();
 		case oldaskconfig:
 			fflush(stdout);
-			fgets(line, 128, stdin);
+			xfgets(line, 128, stdin);
 			strip(line);
 			if (line[0] == '?') {
 				print_help(menu);
@@ -644,3 +644,14 @@
 	}
 	return 0;
 }
+/*
+ * Helper function to facilitate fgets() by Jean Sacren.
+ */
+void xfgets(str, size, in)
+	char *str;
+	int size;
+	FILE *in;
+{
+	if (fgets(str, size, in) == NULL)
+		fprintf(stderr, "\nError in reading or end of file.\n");
+}