fs_mgr: Fix disable-verity for verifyatboot partitions

This allows a remount to be performed on partitions which have been
verified at boot, without causing the verity service to complain of
"corrupted" blocks that could have been modified as a result of a
remount (while the verity checksum remained unchanged).

(cherry picked from commit dd78ae75ff91f19106a4c3944fe3170602ac2334)

Bug: 32638755
Test: Compile
Change-Id: I77cf7dd20ee5c5f5dac80f73f292e32583fe5906
diff --git a/fs_mgr/fs_mgr_verity.cpp b/fs_mgr/fs_mgr_verity.cpp
index efe3fd6..d43c756 100644
--- a/fs_mgr/fs_mgr_verity.cpp
+++ b/fs_mgr/fs_mgr_verity.cpp
@@ -825,7 +825,7 @@
     char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)];
     const char *mount_point;
     char propbuf[PROPERTY_VALUE_MAX];
-    char *status;
+    const char *status;
     int fd = -1;
     int i;
     int mode;
@@ -875,9 +875,13 @@
         verity_ioctl_init(io, mount_point, 0);
 
         if (ioctl(fd, DM_TABLE_STATUS, io)) {
-            ERROR("Failed to query DM_TABLE_STATUS for %s (%s)\n", mount_point,
-                strerror(errno));
-            continue;
+            if (fstab->recs[i].fs_mgr_flags & MF_VERIFYATBOOT) {
+                status = "V";
+            } else {
+                ERROR("Failed to query DM_TABLE_STATUS for %s (%s)\n", mount_point,
+                      strerror(errno));
+                continue;
+            }
         }
 
         status = &buffer[io->data_start + sizeof(struct dm_target_spec)];