docs/specs/tpm: ACPI boot now supported for TPM/ARM

ACPI boot now is supported. Let's remove the comment
saying it is not.
Signed-off-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NStefan Berger <stefanb@linux.ibm.com>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Message-Id: <20200622140620.17229-4-eric.auger@redhat.com>
Tested-by: NArd Biesheuvel <ardb@kernel.org>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

docs/specs/tpm.rst

@@ -346,8 +346,6 @@ In case an Arm virt machine is emulated, use the following command line:
     -drive if=pflash,format=raw,file=flash0.img,readonly \
     -drive if=pflash,format=raw,file=flash1.img
 
-  On Arm, ACPI boot with TPM is not yet supported.
-
 In case SeaBIOS is used as firmware, it should show the TPM menu item
 after entering the menu with 'ESC'.