Stop using the bdev_type and sysfs_block_type SELinux attributes

Stop using these SELinux attributes since the apexd and init SELinux
policies no longer rely on these attributes.

The difference between the previous versions of this patch and the
current patch is that the current patch does not remove any SELinux
attributes. See also
https://android-review.googlesource.com/c/platform/system/sepolicy/+/1850656.
See also
https://android-review.googlesource.com/c/platform/system/sepolicy/+/1862919.

This patch includes a revert of commit 8b2b951349c4 ("Restore permission
for shell to list /sys/class/block").  That commit is no longer necessary
since it was a bug fix for the introduction of the sysfs_block type.

Bug: 202520796
Test: source build/envsetup.sh && lunch aosp_x86_64 && m && launch_cvd
Change-Id: I73e1133af8146c154af95d4b96132e49dbec730c
Signed-off-by: Bart Van Assche <bvanassche@google.com>
7 files changed