Revert "ANDROID: syscall_check: add vendor hook for open syscall"

This reverts commit 996496b8.

If this is needed by any real user, it can easily be reverted to add it
back and then the symbol should be added to the abi list at the same
time to prevent it from being removed again later.

Bug: 203756332
Bug: 191291287
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Change-Id: Ib022789fa899d0e68d1fab3b9e8b39ba053cbc8f
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>