tpm: Correct warning on 32-bit build

Fix the warning:

drivers/tpm/tpm2_tis_sandbox.c: In function ‘sandbox_tpm2_xfer’:
drivers/tpm/tpm2_tis_sandbox.c:288:48: warning: format ‘%ld’ expects
	argument of type ‘long int’, but argument 2 has type ‘size_t’
	{aka ‘unsigned int’} [-Wformat=]
   printf("TPM2: Unmatching length, received: %ld, expected: %d\n",
                                              ~~^
                                              %d
          send_size, length);
          ~~~~~~~~~

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>