quiet down grep/dd output

This removes some spurious noise from the build_image output.

BUG=None
TEST=`./build_image` still worked and is quieter

Change-Id: Ic5d89a462dc137a1a710f77dc16cee401e0083b2
Reviewed-on: https://gerrit.chromium.org/gerrit/35426
Reviewed-by: David James <davidjames@chromium.org>
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>

bin/cros_make_image_bootable

@@ -270,7 +270,8 @@ make_image_bootable() {
           seek=${hash_offset} \
           if="${FLAGS_rootfs_hash}" \
           of="${image}" \
-          conv=notrunc
+          conv=notrunc \
+          status=noxfer
 
   # Move the verification block needed for the hard disk install to the
   # stateful partition. Mount stateful fs, copy file, and umount fs.
@@ -282,7 +283,7 @@ make_image_bootable() {
 
   local koffset="$(partoffset ${image} 2)"
   sudo dd if="${FLAGS_output_dir}/vmlinuz.image" of="${image}" \
-    conv=notrunc bs=512 seek=${koffset}
+    conv=notrunc bs=512 seek=${koffset} status=noxfer
 
   # Update the bootloaders.  The EFI system partition will be updated.
   local kernel_part=
@@ -330,7 +331,7 @@ make_image_bootable() {
     info "copy the squashfs to the partition"
     local part_offset="$(partoffset ${image} 3)"
     sudo dd bs=512 if="${squashfs_img}" of="${image}" \
-            seek=${part_offset} conv=notrunc
+            seek=${part_offset} conv=notrunc status=noxfer
     sudo rm "${squashfs_img}"
   fi
 }
@@ -341,7 +342,8 @@ verify_image_rootfs() {
 
   local rootfs_tmp_file=$(mktemp)
   trap "rm ${rootfs_tmp_file}" EXIT
-  sudo dd if="${image}" of="${rootfs_tmp_file}" bs=512 skip="${rootfs_offset}"
+  sudo dd if="${image}" of="${rootfs_tmp_file}" bs=512 skip="${rootfs_offset}" \
+          status=noxfer
 
   # This flips the read-only compatibility flag, so that
   # e2fsck does not complain about unknown file system capabilities.

mount_gpt_image.sh

@@ -80,7 +80,7 @@ unmount_image() {
   # Don't die on error to force cleanup
   set +e
   # Reset symlinks in /usr/local.
-  if mount | egrep ".* ${FLAGS_stateful_mountpt} .*\(rw,"; then
+  if mount | egrep -q ".* ${FLAGS_stateful_mountpt} .*\(rw,"; then
     setup_symlinks_on_root "/usr/local" "/var" \
       "${FLAGS_stateful_mountpt}"
     fix_broken_symlinks "${FLAGS_rootfs_mountpt}"

update_bootloaders.sh

@@ -90,30 +90,30 @@ if ! type -p update_x86_bootloaders; then
         -e "s|DMTABLEB|${grub_dm_table_b}|g" \
         -e "s|cros_legacy|${cros_flags}|g" \
         "${template_dir}"/efi/boot/grub.cfg |
-        sudo dd of="${esp_fs_dir}"/efi/boot/grub.cfg
+        sudo dd of="${esp_fs_dir}"/efi/boot/grub.cfg status=noxfer
     sed -e "s|/dev/\\\$linuxpartA|${root_a_uuid}|g" \
         -e "s|/dev/\\\$linuxpartB|${root_b_uuid}|g" \
         "${template_dir}"/efi/boot/grub.cfg |
-        sudo dd of="${esp_fs_dir}"/efi/boot/grub.cfg
+        sudo dd of="${esp_fs_dir}"/efi/boot/grub.cfg status=noxfer
 
     # Rewrite syslinux DM_TABLE
     syslinux_dm_table_usb=${dm_table//${old_root}/${root_a_uuid}}
     sed -e "s|DMTABLEA|${syslinux_dm_table_usb}|g" \
         -e "s|cros_legacy|${cros_flags}|g" \
         "${template_dir}"/syslinux/usb.A.cfg |
-        sudo dd of="${esp_fs_dir}"/syslinux/usb.A.cfg
+        sudo dd of="${esp_fs_dir}"/syslinux/usb.A.cfg status=noxfer
 
     syslinux_dm_table_a=${dm_table//${old_root}/HDROOTA}
     sed -e "s|DMTABLEA|${syslinux_dm_table_a}|g" \
         -e "s|cros_legacy|${cros_flags}|g" \
         "${template_dir}"/syslinux/root.A.cfg |
-        sudo dd of="${esp_fs_dir}"/syslinux/root.A.cfg
+        sudo dd of="${esp_fs_dir}"/syslinux/root.A.cfg status=noxfer
 
     syslinux_dm_table_b=${dm_table//${old_root}/HDROOTB}
     sed -e "s|DMTABLEB|${syslinux_dm_table_b}|g" \
         -e "s|cros_legacy|${cros_flags}|g" \
         "${template_dir}"/syslinux/root.B.cfg |
-        sudo dd of="${esp_fs_dir}"/syslinux/root.B.cfg
+        sudo dd of="${esp_fs_dir}"/syslinux/root.B.cfg status=noxfer
 
     # Copy the vmlinuz's into place for syslinux
     sudo cp -f "${template_dir}"/vmlinuz "${esp_fs_dir}"/syslinux/vmlinuz.A