remove inprocess tethering

The logic dealing with in vs out-of-process tethering flags
was added in aosp/master once it was already not merging to tm-dev,
thus ending up only in udc-dev, it was later removed in aosp/master,
and then cherrypicked to udc-dev.

As such there is no shipping version of the bpfloader
(besides early U developer previews and betas)
with this requirement.

Ignore-AOSP-First: change must land in U first,
since it's not safe if it isn't approved for udc-dev

Test: TreeHugger
Bug: 279942846
Signed-off-by: Maciej Żenczykowski <[email protected]>
Change-Id: If7c3ca47891d53f478f7b784580efb2a0014c617

bpfloader/BpfLoader.cpp

@@ -258,9 +258,6 @@ int main(int argc, char** argv) {
         return 1;
     }
 
-    // Tethering mainline module must provide this or U bpfloader will fail to boot.
-    if (!exists("/apex/com.android.tethering/etc/flag/out-of-process")) return 1;
-
     // Linux 5.16-rc1 changed the default to 2 (disabled but changeable), but we need 0 (enabled)
     // (this writeFile is known to fail on at least 4.19, but always defaults to 0 on pre-5.13,
     // on 5.13+ it depends on CONFIG_BPF_UNPRIV_DEFAULT_OFF)