OvmfPkg/Tcg2ConfigPei: factor out InternalTpm12Detect()

Move the calls to the Tpm12RequestUseTpm() and Tpm12SubmitCommand()
Tpm12DeviceLib functions to a separate C file, so that we can override
these actions in a subsequent patch.

This code movement requires moving the TPM_RSP_GET_TICKS / TestTpm12()
helper structure / function too.

While at it, give the TestTpm12() function @retval / @return
documentation, plus wrap an overlong line in it.

Functionally, this patch is a no-op.

Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Simon Hardy <simon.hardy@itdev.co.uk>
Cc: Stefan Berger <stefanb@linux.ibm.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2728
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200520225841.17793-3-lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@arm.com>

OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf

@@ -21,6 +21,8 @@
 
 [Sources]
   Tcg2ConfigPeim.c
+  Tpm12Support.c
+  Tpm12Support.h
 
 [Packages]
   MdePkg/MdePkg.dec