Revert "ANDROID: GKI: Add script to generate symbol protection headers"

This reverts commit 31d5735b.

Reason for revert: Part of old protected/unprotected module implemenation.
It is being replaced by a new design listed as option 2A at
go/gki-modules-build-integration

Bug: 232430739
Test: TH
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Change-Id: I649c57196b167d9452e5e6d3b2af2dd8c1d4bcdd