Drop use of --removable flag to grub-install from buildd/hooks

This now matches the cloud images (7c760864fd)
fixing bootloader updates in the buildd images, but also fixing
compatibility with using devtmpfs for losetup.

debian/changelog

@@ -1,3 +1,13 @@
+livecd-rootfs (2.839) UNRELEASED; urgency=medium
+
+  * Drop use of --removable flag to grub-install from
+    live-build/buildd/hooks/02-disk-image-uefi.binary, to match the cloud
+    images (7c760864fdcb278ca37396f06f5e3f297428d63d).  This fixes
+    bootloader updates in the buildd images, but also fixes compatibility
+    with using devtmpfs for losetup. 
+
+ -- Steve Langasek <steve.langasek@ubuntu.com>  Wed, 17 May 2023 09:25:55 -0700
+
 livecd-rootfs (2.838) mantic; urgency=medium
 
   * auto/config: Set FLAVOUR appropriately for flavours added since the

live-build/buildd/hooks/02-disk-image-uefi.binary

@@ -102,19 +102,9 @@ install_grub() {
         --boot-directory=/boot \
         --efi-directory=/boot/efi \
         --target=${efi_target} \
-        --removable \
         --uefi-secure-boot \
         --no-nvram
 
-    if [ -f mountpoint/boot/efi/EFI/BOOT/grub.cfg ]; then
-        sed -i "s| root| root hd0,gpt1|" mountpoint/boot/efi/EFI/BOOT/grub.cfg
-        sed -i "1i${IMAGE_STR}" mountpoint/boot/efi/EFI/BOOT/grub.cfg
-        # For some reason the grub disk is looking for /boot/grub/grub.cfg on
-        # part 15....
-        chroot mountpoint mkdir -p /boot/efi/boot/grub
-        chroot mountpoint cp /boot/efi/EFI/BOOT/grub.cfg /boot/efi/boot/grub
-    fi
-
     if [ "$ARCH" = "amd64" ]; then
         # Install the BIOS/GPT bits. Since GPT boots from the ESP partition,
         # it means that we just run this simple command and we're done