igc: Fix the typo in the PTM Control macro

The IGC_PTM_CTRL_SHRT_CYC defines the time between two consecutive PTM
requests. The bit resolution of this field is six bits. That bit five was
missing in the mask. This patch comes to correct the typo in the
IGC_PTM_CTRL_SHRT_CYC macro.

Fixes: a90ec848

 ("igc: Add support for PTP getcrosststamp()")
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Link: https://lore.kernel.org/r/20230821171721.2203572-1-anthony.l.nguyen@intel.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>