Revert "Staging: android: binder: Allow using highmem for binder buffers"

This reverts commit c7c95029194484d699fb2c6f2d268b1b4072c784.
Revert "Staging: android: binder: Fix memory leak on thread/process exit"

This reverts commit 2ae1d9fb0b660cf33b9189ec644a2a02bf58e75c.
Revert "staging: android: Avoid using camelcase in binder.h"

This reverts commit 3ab78d66bb43a79b20ea9f18514c297ca1e589f3.