Removing bootdevice from /dev/block/bootdevice/by-name/*

We should switch to use /dev/block/by-name/<partition> because there is
no requirement to have a single 'bootdevice' for Android. The symlink is
created in the following change:

  https://android-review.googlesource.com/c/platform/system/core/+/674989

Bug: 80466341
Test: m -j mkdtimg ufdt_verify_overlay_host && ./verifyDTBO.sh
Change-Id: Ic4464307d54f0119d0c04c2d555f8cc36b6d13e5