EdkShellPkg/ShellR64.patch: Adding missing files from the patch

EdkShellPkg/ShellR64.patch: Adding missing files from the patch

Some files were missing from the newly generated patch:
- Library/Aarch64/efilibplat.h
- Library/Arm/efilibplat.h

Instructions have been written to correctly generate this patch:
https://sourceforge.net/apps/mediawiki/tianocore/index.php?title=ArmPkg/Binaries#EdkShellPkg

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15113 6f19259b-4bc3-4df7-8a09-765794883524