tools/power/x86/intel-speed-select: Fix a read overflow in isst_set_tdp_level_msr()

The isst_send_msr_command() function will read 8 bytes but we are
passing an address to an int (4 bytes) so it results in a read overflow.

Fixes: 3fb4f7cd ("tools/power/x86: A tool to validate Intel Speed Select commands")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>