Documentation: Fix int/unsigned int comparison

Documentation: Fix int/unsigned int comparison

Signed int - unsigned int comparison fixed in mpssd, prctl, ptp, and
timers in Documentation. In places where 'int argc' and 'const char
**argv' are not used, they are replaced with void

Documentation/mic/mpssd/mpssd.c: Fixed comparison in sum_iovec_len and
disp_iovec

Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c: main signature
changed to void, as parameters 'argc' and 'argv' are never used

Documentation/prctl/disable-tsc-on-off-stress-test.c: main signature
changed to void

Documentation/prctl/disable-tsc-test.c: main signature changed to void

Documentation/ptp/testptp.c: Sign comparison fix
Documentation/timers/hpet_example.c: Sign comparision fix

Signed-off-by: Mahesh Khanwalkar <maheshkhanwalkar@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>