BaseTools: Add authenticated variable store support

BaseTools: Add authenticated variable store support

In order to support secure boot with authenticated type variable store
and non secure boot with normal type variable store, add one flag to
switch them.

User can append '-D VPD_AUTHENTICATED_VARIABLE_STORE' to build command
to enable authenticated type varaible store.

Also, user can add 'VPD_AUTHENTICATED_VARIABLE_STORE = TRUE/FALSE' to the
defines section of Dsc file to switch authenticated/normal type variable
store.

VPD_AUTHENTICATED_VARIABLE_STORE is a new reserved key word for this function.

Signed-off-by: Chen Lin Z <lin.z.chen@intel.com>
Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Reviewed-by: Bob Feng <bob.c.feng@intel.com>