fs_mgr: Fix __ANDROID_RECOVERY__ usage in libfiemap.

Certain code in libfiemap should be unreachable in recovery/ramdisk
builds, but whether intentionally or not, __ANDROID_RECOVERY__ is not
working in vendor_boot.

To make sure this is doing exactly what we want, use __ANDROID_RAMDISK__
instead.

Bug: 205987817
Test: build boot, vendor_boot, recovery
Change-Id: Id419f7d9068e791427a896c22569ae4543548df7
diff --git a/fs_mgr/libfiemap/image_manager.cpp b/fs_mgr/libfiemap/image_manager.cpp
index 7ccdbf9..c416f4d 100644
--- a/fs_mgr/libfiemap/image_manager.cpp
+++ b/fs_mgr/libfiemap/image_manager.cpp
@@ -79,7 +79,7 @@
     partition_opener_ = std::make_unique<android::fs_mgr::PartitionOpener>();
 
     // Allow overriding whether ImageManager thinks it's in recovery, for testing.
-#ifdef __ANDROID_RECOVERY__
+#ifdef __ANDROID_RAMDISK__
     device_info_.is_recovery = {true};
 #else
     if (!device_info_.is_recovery.has_value()) {
@@ -523,7 +523,7 @@
 
     auto image_header = GetImageHeaderPath(name);
 
-#if !defined __ANDROID_RECOVERY__
+#ifndef __ANDROID_RAMDISK__
     // If there is a device-mapper node wrapping the block device, then we're
     // able to create another node around it; the dm layer does not carry the
     // exclusion lock down the stack when a mount occurs.