tpm_tis: convert tpm_tis_show_buffer() to use trace event

tpm_tis: convert tpm_tis_show_buffer() to use trace event

cppcheck reports:

[hw/tpm/tpm_tis.c:113]: (warning) %d in format string (no. 2) requires 'int' but the argument type is 'unsigned int'

Rather than just converting the format specifier to use '%u", the
tpm_tis_show_buffer() function is converted to use trace points and
the two debug callers use the trace event infrastructure so that it's
available in production cases also and not just when DEBUG_TIS is enabled.

Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>