ext4_utils: Fix return value in e4crypt_policy_get

Change-Id: I9e02cda707b551980683895ef7f22522157628d8
diff --git a/ext4_utils/ext4_crypt.cpp b/ext4_utils/ext4_crypt.cpp
index 97f255c..d594a48 100644
--- a/ext4_utils/ext4_crypt.cpp
+++ b/ext4_utils/ext4_crypt.cpp
@@ -149,7 +149,7 @@
     if (ioctl(fd, EXT4_IOC_GET_ENCRYPTION_POLICY, &eep) != 0) {
         PLOG(ERROR) << "Failed to get encryption policy for " << directory;
         close(fd);
-        return -1;
+        return false;
     }
     close(fd);